The Crusade (autumn, winter 2013-14)

How is it possible that your city was captured? According to the rules, there should be a rematch, otherwise it's just absurd.

No, everything is correct "according to the rules" - I've encountered this situation many times, and it has been discussed repeatedly. However, "in spirit" - I don't know, capturing buildings is one thing, but according to the rules, a Battle means a rematch, and nothing more, so I'm not arguing.
1.2. Rematch after the first encounter up to turns 115-116-117 inclusive for fast, medium, and slow maps, respectively.
An encounter is considered a direct contact between players, i.e., any battle between them (a battle between any heroes, a battle with the garrison of an enemy castle or mine).