Margaret Warren was born circa 1425 at of Ightfield, Shropshire, England. If the marriage, as estimated, took place in 1445, this would make Margaret a suitable age 20 at the time.
Margaret Warren married William Mainwaring. 
Based on the birth of grandson John in 1475, place the birth of Thomas Mainwaring at 1450. Since he was the second son, place the first at 1448, a daughter at 1446, and the marriage to William at 1445.
Margaret Warren has been shown as the wife of the following husbands as well, however, these are not mentioned in Richardson and there is no other evidence of their marriage:
Margaret and William were the parents of:
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On 23 Dec 2015 at 19:27 GMT Rick Pierpont wrote:
Margaret is 18 degrees from Kevin Bacon, 20 degrees from Cindy Lesure, 20 degrees from Bonnie Thornton and 16 degrees from Queen Elizabeth II Windsor on our single family tree. Login to find your connection.