We were never FCC vassals, we just have friendly relations with the FCC. I'll put it very simple so you can understand. Acre truly wants to be neutral from the coming wars that are about the hit Strategus. This declaration is making it abundantly clear that we will ally the enemies of any faction that attempts to attack us be it Raven/FCC or Occitan. All we desire out of Strategus at the moment is peaceful trade and expansion through the purchasing of fiefs. Our threat is very clear, if you attempt to make war on us we will put our troop generation, gold, position and armaments to the disposal of your enemies. If Ravens attack us we will join the HOC in attacking you. If Occitan attack us we will 100% back the FCC in this war. If the FCC were to attacks us we would back the Occitans in their invasion. Acre never has made any true lasting enemies so we can afford to take the stance of neutrality unlike you older factions with past grievances. In regard to our declaration of war with the Frisians, it was just business. We needed a home at the time and they were the most vulnerable. We did not expect them to have the backing of big brother Ravens. Logically with our rule solidified it profits Acre little to continue a war with no gain and nothing lost in the face of Frisian barking. I will say this in regards to your threats. Acre are no longer homeless nomads looking for our first fief. Any direct attacks on us would be self defeating as you would bleed you out before you could destroy us and leave other opportunistic parties to attack you. Your enemies are many, ours are few.
TLDR: We aren't vassals to anyone. If you want us to be vassals you can make us.