I belive Madara was behind the past three Shinobi wars and has been puppeteering from the shadows. All the wars happened during his lifetime and hiding, and not surprisingly the wars stopped after his death. There are numbers of reason why he would fan the flame of wars for his own benefit and to achieve his Tsukinome.
He doesn't want the alliance of five shinobi countries. A unified force will be a huge problem to deal with and might deter his plans. Also Madara loathes Hashirama's ideals and vision and he wants to destroy that. Hashirama already tried to unify the villages and we know it didn't went well. We still don't know what happened after that meeting but I think it will soon be revealed.
Destruction of Eddy Village, home of the Uzumaki. It is known that the Uzumaki clan possess knowledge of powerful seals,
Seals that have been passed from the Sage of Six paths. He wants those secrets kept from light because they have potential to stop his plans.
To weaken the villages. With constant war, he could eliminate many threats. When all the heroes dies in wars, only the weak will be left leaving for an easy taking of the Bijuus.
He doesn't want the alliance of five shinobi countries. A unified force will be a huge problem to deal with and might deter his plans. Also Madara loathes Hashirama's ideals and vision and he wants to destroy that. Hashirama already tried to unify the villages and we know it didn't went well. We still don't know what happened after that meeting but I think it will soon be revealed.
Destruction of Eddy Village, home of the Uzumaki. It is known that the Uzumaki clan possess knowledge of powerful seals,
Seals that have been passed from the Sage of Six paths. He wants those secrets kept from light because they have potential to stop his plans.
To weaken the villages. With constant war, he could eliminate many threats. When all the heroes dies in wars, only the weak will be left leaving for an easy taking of the Bijuus.