ELKADER, Iowa — Amid an expanse of undulating farmland, deep in the steep valley carved by the Turkey River, the town of Elkader sits most of the year in remote obscurity. Population 1,200 and gradually shrinking, it is the seat of a county without a single traffic light.

Improbably enough, this community settled by Germans and Scandinavians, its religious life built around Catholic and Lutheran churches, bears the name of a Muslim hero. Abd el-Kader was renowned in the 19th century for leading Algeria’s fight for independence and protecting non-Muslims from persecution. Even Abraham Lincoln extolled him.

This weekend, for the fifth year in a row, Elkader will welcome a delegation of Arab dignitaries to celebrate this rare lifeline of tolerance, spanning continents and centuries. Coming less than three weeks after the Boston Marathon bombings, which the authorities say were committed by two Muslim brothers, the Abdelkader Education Project’s forum stands more than ever for an affirming encounter between the United States and Islam.