How long did the crusades usually take? ?

The Crusades were a series of religious wars between Christians and Muslims started primarily to secure control of holy sites considered sacred by both groups. In all, eight major Crusade expeditions occurred between 1096 and 1291. The bloody, violent and often ruthless conflicts propelled the status of European Christians, making them major players in the fight for land in the Middle East. 

so it took about 195 years 

HOPE THIS HELPED °ω°

There were more than 9 crusaded that lasted over 200 years. The first crusade, known as the Reconquista began in 718 CE, and the final crusaded didn’t end until the 15c.

Political forces often influence public opinion.

It can provide a social code to protect each citizen's future economical earnings. and then obviously defending the country from invading countries.