From July 25th  until August 2nd  1909, Barcelona experienced one of the bloodiest episodes in its history, not the only one but probably the  most famous, the Tragic Week.
The trigger was the call of the reservists to join ranks in  then nascent war in Morocco which would last until 1927.
No, I will not give you a lecture on the topic. On the Internet you will find all the information, and much better than I could give to you, today I wish share some postcards and photos I have about those facts as a  video.
I hope you find it at least interesting.

More info about the Tragic Week in wikipedia