Complex sentence: It was not until the end of the 16th century that "Honduras" was used for the whole province and prior to 1580, "Honduras" only referred to the eastern part of the province, and "Higueras" referred to the western part.
Split into simpler sentences: It was not until the end of the 16th century that "Honduras" was used for the whole province. Prior to 1580, "Honduras" only referred to the eastern part of the province, and "Higueras" referred to the western part.