William Gilbert McKellar was born in 1811 in Middlesex, England. He came to Australia at the age of 40, in October 1852, on the Cossipore. He brought with him his wife Maria Esther née Jones, five sons and two daughters.
He was a councillor and first chairman of the Shire of South Barwon. He served from 1857-1860. He was on the committee of the Chamber of Commerce from 1855 to 1861 and was chairman in 1860. He was a director of the Geelong branch of the Bank of New South Wales. He was on the management committee of the Liverpool & London & Globe Insurance Co. when the Geelong office was established.
He lived at Fernside, a property of 10 acres in Highton. He returned to England in May 1861 with some of his family and spent the final years of his life in England, dying at Weston-Super-Mare in January 1898 at the age of 85 years.