Island in the Sea of Time - S. M. Stirling

It's spring on Nantucket and everything is perfectly normal, until a sudden storm blankets the entire island. When the weather clears, the island's inhabitants find that they are no longer in the late 20th century, but have been transported instead to the Bronze Age. Now they must learn to survive with suspicious, warlike peoples they can barely understand and deal with impending disaster, in the shape of a would-be conqueror from their own time.

Utterly engaging...a page-turner that is certain to win the author legions of new readers and fans.--George R. R. Martin, author of A Game of Thrones It's spring on Nantucket and everything is perfectly normal, until a sudden storm blankets the entire island.

When the weather clears, the island's inhabitants find that they are no longer in the late twentieth century...but have been transported instead to the Bronze Age Now they must learn to survive with suspicious, warlike peoples they can barely understand and deal with impending disaster, in the shape of a would-be conqueror from their own time.