Trade League members and call to war

Hey,

was wondering how exactly are trade league members be called to war?

1) Is it like the HRE (emperor can call his allies), so in this case does the trade league leader has to call them?

2) Is the trade league like a normal alliance, so everyone in the league will get a call to war from the nation beeing attacked?

In my case, Venice is trade leauge leader existing of Venice, the knights, mantua and lucca. Venice is also helping in a war at the moment. I want to attack the knights, because venice can't help them at the moment (i know that venice will be called in once they peace out of my war). So my question is, does venice has to call in for lucca and mantua or are they called by the knights?

Tags: http://ringtonedownloads.mobi/country-ringtones/, http://ringtonedownloads.mobi/