LESS than a mile from the Syrian frontier, in the land of Kemal Ataturk, Ahmed Sheikh Said defies the identities that borders inspire.

Mr. Said was born in the Syrian town of Azaz and raised across a line on the map in Kilis, Turkey. A grocer, he speaks Turkish like a native to his customers, while holding an ear open to the Arabic telecasts of Al Jazeera playing in his store. His wife and his mother are Turkish, but Arab blood runs through his veins, he says, “till the end of time.”

“The bread of Azaz comes from Kilis, and the bread of Kilis comes from Azaz,” said Mr. Said, whose shop sits just off a road that once carried the business of the far-flung Ottoman Empire and now marks Turkey’s limits. “We’re the same. We’re brothers. What really divides us?”

As the Arab world beyond the border struggles with the inspirations and traumas of its revolution — a new notion of citizenship colliding with the smaller claims of piety, sect and clan — something else is percolating along the old routes of that empire, which spanned three continents and lasted six centuries before Ataturk brought it to an end in 1923 with self-conscious revolutionary zeal.

It is probably too early to define identities emerging in those locales. But something bigger than its parts is at work along imperial connections that were bent but never broken by decades of colonialism and the cold war. The links are the stuff of land, culture, history, architecture, memory and imagination that remains the realm of scholarship and daily lives but often eludes the notice of a journalism marching to the cadence of conflict....