Oswald Grundy was the fourth son of textile merchant George Grundy. Born in the Cheetham Hill area of Manchester, he joined his father's business, Grundy and Beardoe, in around 1829. He sailed to Valparaiso, Chile, in 1829 to act as a textile agent for his father's business. While living in Chile, he kept a detailed journal of his activities and the shipping trade at Valparaiso. He returned home to Manchester in 1848 and remained in the city until 1856. During this period, he set up his own business, following his father's death in 1849, trading as Oswald Grundy & Co. He left Manchester for Canada in 1856, settling in Ontario, where he worked as a farmer, initially near Cobourg and later near Niagara Falls. He died in Toronto in 1897.