At the 1685 English general election Erle was returned unopposed again, and was named to committees in Parliament but was called away in response to Monmouth's invasion.

Erle took command of the East Dorset militia as major, and fought as a volunteer at the Battle of Sedgemoor with his friend Thomas Chafin.

[3] In 1686, Erle hosted a group of conspirators who met at Charborough House to plan the overthrow of "the tyrant race of Stuarts".

He was promoted to colonel of a foot regiment and on 8 March 1689 was sent to Ireland to fight the combined French and Irish Army of the deposed King James II of England.

Erle was again involved in the management of the mutiny bill, he signed the Association, and voted with the Court in March 1696 to fix the price of guineas at 22 shillings.

He voted for the attainder of Sir John Fenwick on 25 November 1696 and spoke against a reduction of the military establishment on 8 January 1698.

Erle supported the Court choice of Speaker on 25 October 1705 and was named to the drafting committee on the mutiny bill on 23 January 1706.

[4] In January 1707, Erle took part in an expedition to Spain, fighting in the Battle of Almanza on 23 April 1707 – some reports state that he lost his right hand.

During the debate on the deficiency of English troops at Almanza, Erle defended Lord Galway, the commander, in the Commons on 24 February 1708.

The expedition was late in starting and the plan to land at St Valery to capture Abbeville was abandoned.

The force eventually landed at Ostend and set up an outpost at Leffingham, which fell to the French without a fight on 16 October 1708.

In spite of the failure, when Erle returned home in December 1708, he was appointed commander-in-chief of land forces in England.

The same year, he was also made Governor of Portsmouth, replacing Lord North and Grey, whose loyalty to the new king was in doubt.

He was forced to resign all his posts and his seat in Parliament in March 1718 and received in return a pension of £1,200 a year.