The new President was thirty-five years old, good-looking, careful of his appearance, fond of military finery, and strutted as he walked. He spoke French and Spanish fluently, but with his officers and men used only Guarany. He was an eloquent speaker and had the gift of inspiring his troops with confidence in himself and contempt for the enemy. He had a will of iron; his pride was intense; he was absolutely unscrupulous, and had no regard for the truth. He never showed any feeling of kindness to his most devoted subjects. He ordered his best friends to execution; he tortured his mother and sisters and murdered his brothers. The only natural affection he ever evinced was a fondness for Madame Lynch, a woman whom he had picked up in Paris, and for her children. He seems to have treated her well to the last, but his numerous other mistresses and their children he heartlessly abandoned. Though physically an arrant coward, no defeats could discourage him. He fought to the last against overwhelming odds and was able to retain his personal ascendancy over his followers, even after he had been driven into the woods and all reasonable hope was lost.

He began his reign like a Mahometan sultan by ridding himself of his father's most trusted counsellors, imprisoning and executing the most intelligent and powerful citizens, and banishing his brothers. The military preparations which he had begun as his father's Minister of War were continued with increased vigour. The warlike Argentines and Uruguayans and the powerful empire of Brazil laughed at his pretensions to become a real factor in South American international affairs, but their laughter soon cost them dear. He was a monarch of a compact little state whose position behind rivers in the centre of the continent made it admirably defensible. Its eight hundred thousand inhabitants were obedient, brave, and physically vigorous. Accustomed for generations to regard their dictator as the greatest ruler in the world, knowing no duty except absolute compliance with his will, they never doubted that under his leadership they would be invincible. He knew that he could raise an army out of all proportion to the size of his country. The problem was how to arm it. With Buenos Aires commanding the only route of ingress from abroad it had been difficult for his father and himself to obtain war material from Europe. For years, however, they had been buying all that they could and had accumulated several hundred cannon, most of them antiquated cast-iron smooth-bores. They had fortified the point of HumaitÁ which admirably protected the Paraguay River from naval attacks, and had established an arsenal at Asuncion.

Against Brazil Lopez had serious cause of complaint. The boundary question was still unsettled and his possession of the Lower Paraguay placed the great province of Matto Grosso at his mercy, while the existence of that province, geographically a mere northern extension of Paraguay, was a menace to his own safety. Against the Argentines his hatred was not so well founded, but none the less bitter.

The usual civil war was going on in Uruguay in 1863. The party which held the capital was out of favour at Rio and at Buenos Aires, and Brazil and Argentine were both inclined to support the pretensions of FlorÉs, who led the revolutionists. Lopez thought that his own interests were concerned and asserted his right to be consulted as to Uruguayan affairs. A mighty shout of laughter went up from the Buenos Aires press at the pretensions of the cacique of an Indian tribe to the position of guardian of the equilibrium of South America. Brazil ignored his protests and calmly went on with her preparations to establish her protÉgÉ in Montevideo. In the beginning of 1864 Lopez began active preparations for war. His army already numbered twenty-eight thousand men, and by the end of August sixty-four thousand more had been enrolled and drilled. Although ill provided with artillery and horses, and although the infantry were mostly armed with old-fashioned flintlocks, no such formidable force had ever assembled in South America. The news of Lopez's preparations exasperated and somewhat alarmed the people of Buenos Aires, though no one knew his exact intentions. Lopez had, in fact, determined to compel the Brazilian and Argentine governments to accept his wishes as to Uruguay or to risk all in the hazard of war. Perhaps hazy dreams of himself as emperor of a domain extending from the southern sources of the Amazon far down the Plate valley and over to the Atlantic coast passed through his brain. Possibly he foresaw clearly that Paraguay had come to the parting of the ways, and that she must either fight her way to the sea or reconcile herself to slow suffocation between the immense masses of Brazil and Argentina. In such a contest the only allies he could hope for would be revolutionary factions in Uruguay and Corrientes, and possibly the virtually independent ruler of Entre Rios. In case of a war with Brazil alone, the neutrality of Argentina might have been secured by careful management, but in the freer countries the feeling against him as a despot was strong, and the extension of his system would have been regarded as a menace to civilisation.

Late in 1864 the Brazilian forces marched into Uruguay and joined FlorÉs. Lopez promptly retaliated by seizing a Brazilian steamer which was passing Asuncion on its way to Matto Grosso and followed up this aggression by an invasion of the latter province. His forces quickly reduced the towns on the banks of the Paraguay as far as steamers could penetrate. It was impossible to send reinforcements overland from Rio; Brazil's counter-attack must be delivered from the south. The empire was unprepared, but its troops poured into Uruguay and Rio Grande as fast as they could be mobilised. The anti-FlorÉs party were crushed by the siege and capture of Paysandu late in 1864. The Argentine government under Mitre proclaimed its neutrality. Lopez was flushed with his easy success in Matto Grosso. The forces he had on foot overwhelmingly outnumbered those of the Brazilians in Uruguay and Rio Grande. He wished to strike the latter before they could be re-enforced, overrun Rio Grande, and, as master of one of Brazil's most valuable provinces, dictate terms. To reach the Brazilians it was necessary to cross the Argentine province of Corrientes. He asked for permission to do so and Mitre refused. Notwithstanding the risk involved, he promptly decided to finish up both Argentine and Brazil at the same time. Sending his troops across the ParanÁ he virtually annexed Corrientes and declared war on Buenos Aires. Lopez destined twenty-five thousand men for the invasion of Corrientes and the conquest of the Lower Uruguay valley, but the difficulties of getting so large an army across the river and ready for an advance into a hostile country were unexpectedly great. The gauchos of Corrientes, trained for generations in civil wars, quickly assembled to oppose the Paraguayans. Meanwhile, a Brazilian fleet came up; and, on June 2, 1865, at Riachuelo, decisively defeated the Paraguayan naval forces. Lopez thereby lost all hope of commanding the river. The communications of his army in Corrientes might be cut off at any time and an advance became impossible. The battle of Riachuelo threw Paraguay on the defensive and made Lopez's great plan of carrying the war to the Uruguay impracticable.

Nevertheless, Lopez did not recall the twelve thousand men he had sent across the missions to invade the valley of the Upper Uruguay and the state of Rio Grande. The Brazilians were taken unprepared, and early in August the Paraguayans had captured the chief Brazilian town in that region—Uruguayana. The failure of the Corrientes army to reach the Lower Uruguay left the route up that river free. The Brazilian and Uruguayan army, which had been victorious at PaysandÚ, marched up the west bank and defeated and destroyed the rear-guard which the Paraguayans had left on the Argentine side opposite Uruguayana. Lopez's army was therefore cut off from retreat. It was promptly surrounded, and on the 17th of September, 1865, had to surrender.

This put an end to Lopez's plan of an offensive campaign. Indignant at the invasion of her soil, Argentina had allied herself with Brazil against him. A secret treaty was signed between Brazil, Argentina, and FlorÉs, now recognised as ruler of Uruguay, to prosecute the war to a finish, to depose Lopez from his throne, and to disarm the Paraguayan fortifications. Lopez withdrew his army from Corrientes and concentrated all his forces in the south-west angle of his own territory.

The position was admirable for defence. North of the ParanÁ and east of the Paraguay stretched a low, wooded country subject to overflow, and intersected by shallow, mud-bottomed lagoons, which were old abandoned beds of the rivers. The Paraguay protected his right flank and afforded him a direct and easy communication with Asuncion. Batteries on the point of HumaitÁ, which the Brazilian fleet did not dare to try to pass, insured this line of communication. West of the Paraguay the great Chaco, there impenetrable, prevented a movement to get north of HumaitÁ on that side. To the east the swamps along the ParanÁ extended indefinitely, and an advance of the enemy in that direction would have had its communications cut by an army encamped near HumaitÁ. HumaitÁ was, therefore, the key to the situation, and the allies could not advance until they captured it or, by running the batteries with their fleet, destroyed Lopez's control of the Paraguay.

By March, 1866, the allies had concentrated a force of forty thousand men just south of the fork of the rivers. About twenty-five thousand were Brazilians, twelve thousand Argentines and three thousand Uruguayans. The Brazilian fleet, numbering eighteen steam gunboats carrying one hundred and twenty-five guns, lay near at hand ready to co-operate. Protected by the fire of the gunboats, the whole allied army had little difficulty in crossing the ParanÁ and establishing itself on Paraguayan soil. Lopez lost heavily in vain attempts to prevent this landing. On May 2nd, a force of Paraguayans surprised the allies a few miles north of the river and badly cut up the vanguard. The allies, however, continued advancing and took a strong position just south of a great lagoon. Here, on the 24th of May, they were attacked by the whole Paraguayan army of twenty-five thousand men, who fought with desperate valour, but at a hopeless disadvantage. A quarter of the Paraguayan soldiers were left dead on the field, and another quarter were badly wounded, while the loss of the allies was half as great. The Paraguayan army was apparently destroyed, but the allies had suffered so severely, and the difficulties of transportation through the swamps were so great, that they did not make the sudden dash upon the trenches at HumaitÁ which might have ended the war. Lopez did his utmost to reorganise his army. Practically the whole male population was impressed into service. The river line of communication to Asuncion, and the strategic railroad thence up into the most fertile and populous interior of the country, enabled him comfortably to command all the resources of the country, both in men and provisions.

HumaitÁ had already been well fortified on the land side, and Lopez now threw up the trenches at the top of the bluff at Curupayty, the first high land on the Paraguay River north of the allied army and south of HumaitÁ, and connected it with the latter fortress. Lopez had the advantage of the services of a clever English civil engineer; and the fortifications, though rude, were soon made practically impregnable to assault. In spite of their defeats, the Paraguayans were as ready as ever to attack when Lopez commanded, or to stand up and be shot down to the last man. They were the most obedient soldiers imaginable; they never complained of an injustice and never questioned an order when given. Even if a soldier were flogged, he consoled himself by saying, "If my father did not flog me, who would?" Every one called his superior officer his "father," and Lopez was the "Great Father." Each officer was responsible with his life for the faithfulness and conduct of his men and had orders to shoot any that wavered. Each soldier knew that the men who touched shoulders with him right and left were instructed to shoot him if he tried to desert or fly, and those two knew that the men beyond them would shoot them if they failed to kill the poor fellow in the centre of the five. This cruel system answered perfectly with the Paraguayans, and to the very end of the war they never refused to fight steadily against the most hopeless odds.

Meanwhile, the allies awaited reinforcements and supplies in the noisome swamps, dying meantime by thousands of fever. By the end of June, when the allies finally determined to assault the fortifications around HumaitÁ, Lopez had twenty thousand men on the ground. After some bloody and indecisive fighting in the swamps, General Mitre, the Commander-in-Chief, ordered a grand attack upon the entrenchments at Curupayty. On the 22nd of September, 1866, it began with the bombardment by the Brazilian ironclads. Eighteen thousand men in four columns advanced from the south, and threw themselves blindly against the fortifications. When they came to close quarters they were thrown into disorder by the terrible artillery fire from the Paraguayan trenches, which cross-enfiladed them in different directions. The enormous canisters discharged from the eight-inch guns point-blank, at a distance of two or three hundred yards, wrought fearful execution. The rifle fire of the allies was useless, and the Paraguayans simply waited behind their trenches until the Brazilians and Argentines were close at hand and then fired. The allies retired in good order, after suffering a loss of one-third their number. The soldiers obediently kept rushing on to certain death until their officers, seeing that success was hopeless, told them that they might retreat. The courage of the Paraguayans had been proved in their unsuccessful assaults on the allies the year before, and now the Argentines and Brazilians showed even in this awful defeat what a stomach they, too, had for hand-to-hand fighting.

After the battle of Curupayty, nothing was attempted on either side for fourteen months. Both sides had had enough of attacking fortified positions. The Paraguayans lay in HumaitÁ and the allies occupied themselves with fortifying their camps. The imperial government made tremendous exertions to reinforce the army. The Argentines also did their best, but the efforts of both were hardly sufficient to make good the terrible ravages of the cholera, which by the beginning of May, 1867, had put thirteen thousand Brazilians in hospitals. It was not until July that the allies felt themselves again ready to take the offensive. A division marched up the ParanÁ with the purpose of outflanking HumaitÁ on the east, while cavalry raids were sent out to the north and rendered the outlying positions of the Paraguayans unsafe. Finally, in November, 1867, the Brazilian troops succeeded in getting over to the Paraguay River, north and in the rear of Lopez, and General Barreto captured and fortified a strong position on the bank fifteen miles north of HumaitÁ. This was fatal to the security and communications of Lopez. He made one more desperate and unsuccessful assault on the main position of the allies, and then began to plan to retire toward Asuncion. At the same time the Brazilian ironclads passed the batteries at Curupayty, compelling Lopez to withdraw his troops up the river to HumaitÁ. The war became virtually a siege of the latter place, which was constantly bombarded by the fleet from the front and by the army from the rear. The Brazilian position on the river to the north cut Lopez off from direct river communication with Asuncion, and he had to transport his supplies on a new road built in the Chaco swamps. He began preparations to evacuate HumaitÁ and retreat to the north. In January, 1868, Mitre definitely retired from the command of the allies and was succeeded by the Brazilian Marshal Caxias. A month later (February 18th) the Brazilian fleet of ironclads finally succeeded in running the batteries at HumaitÁ, and after throwing a few bombs at Asuncion, devoted themselves to the more useful task of cutting off the transports to Lopez's army.

Lopez's line of river communication was now completely at the enemies' mercy, and a large force could not be maintained at HumaitÁ. He transported his army to the right bank of the Paraguay, recrossing when he got beyond the Brazilian positions. The garrison of three thousand men which he left at HumaitÁ defended itself for six months. In the meantime, he had fortified a new position less than fifty miles from Asuncion and accessible across the country from his base of supplies in central Paraguay. On his right flank a river battery was erected which again prevented the Brazilians from reaching the upper river. Opposite this point, however, the Chaco is penetrable, and Caxias landed a force on the west bank and, marching up, crossed the river in the rear of Lopez's position. The Brazilians closed in from the north and south on the few thousand Paraguayans, who were all that survived, and after several days of desperate fighting, December 27, 1868, the Brazilians carried Lopez's position and he fled for his life to the interior, followed by a thousand men.

Even after such a defeat he was indomitable and succeeded in gathering another small army which was pursued and destroyed in August, 1869. Lopez again escaped and took refuge in the wild and mountainous regions in the north of Paraguay. The Brazilian cavalry pursued him relentlessly, but it was not until March 1, 1870, that he was caught. In an attempt to escape he was speared by a common soldier.