 Edward was the oldest of six siblings, and some of his brothers had distinguished military careers as well, including Lieutenant Colonel William Burke Nicolls (1780 – 1844) of the British Army's 2nd West India Regiment, and Commander Jonathan Frederick Nicolls (1782 – 1845) of the Royal Navy. All five of Edward Nicolls' brothers and both of his sons died in or as the result of public service. Nicolls was educated at a grammar school in Coleraine and at Royal Park Academy near Greenwich prior to entering the Marines on 24 March 1795. He was not yet 16 years old when he received his commission as a second lieutenant in His Majesty's Marine Forces, in 1795, and he was promoted to first lieutenant on 27 January 1796.
