He was the commander at Fort Menaskoux and was attacked during the Northeast Coast Campaign (1724).
From 1683 to 1686 he attended a school at Newington Green (near London) conducted by the Rev.
Removing to Portsmouth, New Hampshire, he there married Mary Cutt, a daughter of John Cutt (1625–1681), president of the Province of New Hampshire in 1679, a successful merchant and mill-owner, and thus came into possession of considerable property (including much of the present site of Portsmouth).
In 1700 he was speaker of the Assembly and in 1702 became a member of the Provincial Council, but was suspended by Lieutenant-Governor George Vaughan (1676–1724).
Penhallow, however, was sustained by Governor Samuel Shute (1662–1742), and Vaughan was removed from office in 1716.