The Rideau Arcott is a purebred sheep that was created entirely in Canada. It was developed over a 30 year period (from 1958 to 1989) by Agriculture Canada at the federal government research station outside Ottawa, using stock mainly from Finnish Landrace, Suffolk and East Friesian breeds, and released to Canadian farms in 1989. The purpose of the Rideau Arcott program was to produce a dam-line breed for crossbreeding that would offer ewes with high fertility, good milking characteristics and good body conformation and growth rate. The breed features very high prolificacy with ewe lambs reaching sexual maturity at seven to eight months and lambing at one year. Because of multiple births, they do require extra management at lambing.