Walter Aselstine was born in Trenton, Ontario, on 23 April 1888, the child of Adelbert Aselstine and Lucy (Wallace). The family moved to Belleville in around 1898 and operated a stage coach business between Belleville and Trenton. Walter Aselstine drove the first motor bus operated by the company. Buses ran between the station and the Hotel Quinte and from Belleville to Marmora and Tweed.
Walter Aselstine was a trombonist who played in the orchestra at the Griffin Opera House and was the sound effects man for silent pictures. He played in the Belleville Municipal Band, the Toronto Kilties Band, Odd Fellows Band and military bands including the Princess Pats and the Shrine Band in Toronto. He was a member of the Commodores orchestra and played on excursion boats on the St. Lawrence River. He was a member of Moira Lodge No. 11 and of Christ Church in Belleville. He married Mae Oliphant and the couple had one son and one daughter. He died in Toronto on 27 February 1968.