Possible Clues:

• 1,051, in old Rome
• XV years before the Battle of Hastings
• Galba's 1051
• Year in the papacy of St. Leo IX
• Mid-11th century date
• Midpoint of the 11th century
• 1051 on monuments
• 1,051 in Roman numerals
• Year before Philip I was born
• Nero's 1,051