Validated by Melissa Page, Lucas was born in Morwenstow and moved to Marhamchurch in 1908. Lucas lived there for the next 40 years, until 1948. He then moved with his family to Poughill, where he continued to live after the 1963 death of his wife, Ivy Nancekivell, whom he married in 1926.
Having two brothers and two sisters, Lucas left school at 14 and was called up for service during World War I and II. He, however, did not serve for either of them due to a heart condition. During the war, Lucas instead helped on his family farm. He bred Devon cattle and Devon longwool sheep and set up a dairy farm in the 1940s.
At 50, Lucas began playing bowls, and did not drop it until he was 100.
He was also a member (and vice-chairman) of Bude Town Council from 1959 to 1970. His daughter stated of him, "He has worked hard in his working life and was a teetotaller and non-smoker and since he has been elderly has been well cared for".
Lucas became the oldest living European male on 25 July 2009 at 109 following the death of 111-year-old Harry Patch, who had earned the title only a week earlier. He was the first European male under 110 to take the title since 1994, when Emile Fourcade took the title on 26 January following the death of Spanish Pablo Roy Morales, who had taken the title just a week earlier and died at the age of 110 years, 11 days.
On 7 June 2010, Lucas entered the list of the top 100 oldest men, excluding disputed cases. He was 110 years, 143 days old at the time.
However, on 21 June 2010, Lucas died, at the age of 110 years, 157 days, without ever entering the top 100 oldest men (with disputed cases included), instead coming to rest at 103rd place. He had been Europe's oldest male for 331 days.