Content-modification system with geographic area-based feature

In one aspect, a method includes identifying a geographic area of a content-presentation device. The method also includes using at least the identified geographic area as a basis to select, from among a plurality of reference fingerprint data sets, a reference fingerprint data set that corresponds with the identified geographic area. The method also includes transmitting to the content-presentation device, the selected reference fingerprint data set that corresponds with the identified geographic area to facilitate the content-presentation device detecting a match between query fingerprint data representing content received by the content-presentation device and at least a portion of reference fingerprint data in the transmitted reference fingerprint data set.