1-(we are watching second half of a football match between England and Germany)
Germany have scored 3 goals so far.
2-(2 weeks after)
Germany scored 4 goals in the match 2 weeks ago.
In the first example we have seen 3 goals by germany since the begining of the match. In your sentence likewise we have had 3 wizards since 1000 years ago.
Student or Learner