Do the Nordic flags have crosses on them?

The flags with crosses on them are the Swiss, Danish, Finnish, Norwegian, Swedish, and Icelandic flags.

In the year 57, there was a war between Sweden and Finland, and Denmark, Iceland, and Norway were swept up in it. At that time, King Eric prayed to God, and a miracle happened, the blue sky was glittering with the light of the cross (actually a natural celestial phenomenon), which symbolizes benevolence for Christianity. So they thought it was a sign from God. So the five Nordic countries turned their differences into friendship and swore an alliance, and all five countries added a cross to their flags.

Origins

The Nordic Cross, or Scandinavian Cross, is a symbol of the Teutonic Knights, which originated in 1192 A.D. It represents a long line of military traditions from the Teutonic Knights. The motto of the Teutonic Order was "Helfen, Heilen, Wehren".

The Nordic Cross was later used on the flags of the Nordic countries, and is now found on all of their flags, but also on the flags of other regions. The cross in the pattern is a Christian symbol. It can be seen as placing the Greek cross (all arms equal in length) in the center of the flag, then moving the cross horizontally towards the flagpole, and then extending the four arms to the edge of the flag.