Pelusium (Persian Conquest of Egypt).
Fought 525 B.C., between the Persians, under Cambyses, and the Egyptians, under Psammeticus. The Egyptians were totally defeated, and this victory was followed by the complete subjugation of Egypt, which became a Persian satrapy.
Pelusium (War of Alexander's Successors).
Fought B.C. 321, between the Macedonians, under the Regent, Perdiccas, and the Egyptians, under Ptolemy Lagus. Perdiccas attacked the fortress, but was driven off with heavy loss, including 1,000 drowned in the Nile.
Peña Cerrada (First Carlist War).
This fortress, held by a Carlist garrison, under Gergue, was captured by Espartero with 19,000 Cristinos, June 21, 1838. After shelling the place for 7 hours, Espartero attacked the Carlists, who held the heights outside the town, and dispersed them, capturing 600 prisoners, and all their guns. The remainder of the garrison then abandoned the place.
Penobscot Bay (American War of Independence).
Fought July 14, 1779, when a British squadron of 10 ships, under Sir George Collier, completely destroyed an American squadron of 24 ships, and captured the 3,000 men who formed their crews.
Pen Selwood (Danish Invasion).
Fought 1016, between the English, under Edmund Ironside, and the Danes, under Knut, shortly after Edmund's election as King by the Witanegemot. This was the first of the series of engagements between the two rivals, which ended with the Peace of Olney.