-Ymir-the-titan died and became 9 other titans of individual will (as far as we know).
-Marley obtained control over 7 of the 9 titans. Those 7 titans were used by Marley to exert military dominance.
-The remaining 2 titans are the Attack Titan and the Founding/Coordinator Titan.
-Coordinator Titan is the King himself, who decided to hole up onMadagascarParadise.
-Attack Titan belonged to the royal family who remained on Marley and tried to form a local resistance.
-Marley is losing military dominance now because technology is slowly rivalling Titans. To maintain military might, they need to obtain the power of the coordinator to:
--------1) diffuse the island's titans as a threat.
--------2) control all titans as an offensive force.
--------3) obtain the island's fossil fuels as a military resource.
If it's not Isuzu-chan Mii~