Historical clue formulations

• 11th-century conquerors — 2015-07-10
• 11th-century invaders — 2011-12-10
• Followers of William the Conqueror — 2011-11-13
• Kings Henry I and Stephen — 2010-01-02
• Rouen residents, e.g. — 2005-06-10
• Some 30-Down inhabitants — 2002-11-09
• 1066 battlers — 1997-02-21
• Conquerors of 1066 — 1994-12-20