Lambert was born in Leicester, into a family of gamekeepers, huntsmen and field sportsmen.
In 1806, having ample time and modest money, Lambert conceived the idea of exhibiting himself for profit. He commissioned a special carriage to take him to London, where he charged five shillings a head for a view of his portly person. He made tours of the country, putting himself on display to the paying public and earned sufficient money to pay his enormous clothing bill.
After some months on public display, Lambert grew tired of exhibiting himself and in September 1806 he returned wealthy to Leicester, where he bred sporting dogs and regularly attended sporting events. Between 1806 and 1809, he made a further series of short fundraising tours.
With his almost celebrity status back in the day he is said to have frequented the pubs in Stamford, challenging persons to a foot race with the stipulation that he was given a small head start. With many narrow passages connecting the main streets of Stamford once Lambert was ahead of his competitors his size made it impossible for anyone to get past him and so he always won.