John Squire (1780–1812) was a British Army officer who rose to become a brevet lieutenant-colonel in the Corps of Royal Engineers during the Napoleonic Wars. Being a writer and diarist who kept journals of his travels, these and his supporting role in some of military campaigning's great moments – Egypt in 1801, South America in 1807, Sweden in 1808, the Netherlands at various stages and Spain in 1811–12 – have made Squire a moderately well-known figure among scholars who study the era.