Sir William Lower was the only son of John Lower, and was born at Tremere, in S. Tudy, about the year 1600.

The Lowers were a very ancient family in Cornwall, seated in S. Winnow parish, and at Clifton, in Landulph, at which latter place lived Sir Nicholas Lower, the brother of John, whilst the eldest brother, Sir William, settled at Treventy, in Carmarthen, having married the daughter and co-heiress of Sir Thomas Pescott, of that place. John had two other brothers knights, Sir Francis and Sir Thomas.

William was not educated at Oxford, but, as Wood says, "spent some time in Oxon, in the condition of hospes, for the sake of the public library and scholastical company." He exhibited a "gay fancy," and a mighty aversion from the dry and crabbed studies of logic and philosophy.

Leaving Oxford, he spent some time in France, where he became a master of the French tongue, and acquired a great admiration for the dramatic compositions of Corneille, Quirault, and Ceriziers, and in after years amused himself with translating some of their plays.

When the troubles broke out in England he took the King's side, and in 1640 was a lieutenant in Sir Jacob Ashley's regiment in Northumberland's army against the Scotch Covenanters, and was then appointed captain, but lost his company, that proved mutinous and deserted. "It was a marvellous thing," says a writer of the time, "to observe the averseness of the common soldiers to this war. Though commanders and gentlemen of great quality, in pure obedience to the King, seemed not at all to dispute the cause or consequence of this war, the common soldiers would not be satisfied, questioning, in a mutinous manner, whether their captains were papists or not, and in many places were not appeased till they saw them receive the sacrament; laying violent hands on divers of their commanders, and killing some, uttering in bold speeches their distaste of the cause, to the astonishment of many, that common people should be sensible of public interest and religion, when lords and gentlemen seemed not to be."

In June, 1644, being a lieutenant-colonel in Thomas Blague's regiment and lieutenant-governor of Wallingford, Lower received orders from the King to raise £50 a week from the town of Reading. Lower at once laid hands on the mayor and carried him to Wallingford as a hostage; he then plied the corporation with demands for the money, without which their head would not be restored to them. The corporation, however, did not value their mayor so highly that they were disposed to pay £50 per week for the privilege of having him restored to them. Lower was taken prisoner by the garrison of Abingdon on 19th January, 1645-6, and Charles rewarded him for his zeal by conferring on him knighthood.

He remained in England for nearly ten more years and saw the ruin of the Royal cause, which he did care for, and of the Church, for which he cared not a rush. In 1655 he quitted England and went to Cologne, which was full of refugees, and there he was cheered with the tidings that Oliver Cromwell was failing in health and had not long to live. Leaving Cologne, after a brief residence there, he "took sanctuary in Holland, where in peace and privacy he enjoyed the society of the Muses," says Langhorn.

His The Phoenix in Her Flames, a tragedy in four acts, had been published in 1639. The Innocent Lady, or the Illustrious Innocence, translated from the French of R. de Ceriziers, was published in 1654. Now in Holland he worked hard at other translations, and he was the more able to do this at ease, as the Princess Royal Mary of Orange seems to have taken him into her retinue at the Hague. If the Court was anything like what it was when James Howell was there, it must have been vastly dull for the lively and dissolute Sir William Lower. But his stay was enlivened by the arrival of Charles and the intrigues there carried on with the well-affected in England.

At the Hague he issued a thin royal folio, with many plates, entitled "A relation in form of Journal of the voiage and residence which the most excellent and most mighty Prince, Charles the II, King of Great Britain, etc., hath made in Holland, from the 25th of May to the 2nd of June, 1660, rendered into English from the original French. By Sir W. Lower, Knt. Printed by Adrian Ulack." This was published in Dutch, French, and English, and at the end of the volume Sir W. Lower inserted his poems, and an apology for the "tardive appearance (of the book) due to those men who grave the plates."

Such "poems" as he has given as his own show conclusively enough that he was not a poet, but a mere hammerer together of rhymes.

In June, 1660, calculating on his services rendered to Charles I and to the sumptuous book on the residence in Holland of Charles II that he had brought out, Lower appealed to Secretary Nicholas from The Hague to obtain for him some place in the King's service. But the death of his cousin Thomas, only son of Sir William Lower, of Treventy, who died on 5th February, 1661, by which he became sole heir, executor, and chief representative of the family, recalled him to England. He did not, however, enjoy ease long, for he died in the ensuing year, 1662, leaving an only child, Elizabeth, who probably died early, for nothing further is known of her than that she was in existence when her father died. Who the wife of Sir William Lower was is not known.

His cousin, Dr. Richard Lower, of S. Paul's, Covent Garden, who gave Wood information relative to his kinsman, described him as "an ill poet and a worse man."

His long residence abroad, his dissociation from Cornwall for all his life save his early boyhood, his separation from his kinsmen, had broken all the ties that linked him to his family and county; and when he inherited the estates and was in a position to assist his kinsmen who had been greatly reduced by the civil wars, "he did not, but followed the vices of poets."