 If you liked Tenkuu no Shiro Laputa |  ...then you might like Shingeki no Kyojin Season 3 |
Both feature an island which had been ruling the world with its extraordinary powers and its war titans for centuries until it found itself in inner conflicts which spared the world from its dominance. The main heroine is a girl who is, unknowingly, a descendant of the island's royal family (a family that was split after the fall of the island) who grew up on a farm as a little girl. Together with the help of the male protagonist, she now has to decide over the future of the island's powers. Not to mention, the start of the Ending song "Akatsuki no Requiem" literally sounds like a