He and his brother John survived the wreck of the Orion in 1850, in which his parents and two sisters lost their lives.[3]
As a member of the Royal Engineers, McNeill participated in the Indian Rebellion of 1857 for the entire conflict. He was wounded in the Siege of Delhi. At Calcutta, he married the daughter of Captain Henry Forrester Leighton; she was also the niece of Sir Archibald Wilson, the commander-in-chief at Delhi.[2]
He retired from the Royal Engineers and came to New Zealand, where he and his brother, Sir Malcolm McNeill, bought Ardlussa Station in Southland. They named it after their family's estate of Ardlussa, on the island of Jura, Scotland.[citation needed]
He represented the Wallace electorate from 1866 to 1869, when he resigned.[4]
From the mid-1880s, he lived in Wanganui, where he died on 17 May 1915. He was buried at Wanganui Cemetery.[2]