Indian Ocean trade Madagascar at this time leaving behind a lasting cultural and genetic legacy. Chinese fleets under Zheng He criscrossed the Indian Ocean during the early part of the 15th century. The missions were diplomatic rather than commercial, but many exchanges of gift and produces were made. The Portuguese under Vasco da Gama discovered a naval route to the Indian Ocean through the southern tip of Africa in 1497–98. Initially, the Portuguese were mainly active in Calicut, but the northern region of Gujarat was even more important for trade, and an essential intermediary in east-west trade. Venetian interests were directly threatened as
Time in Portugal Cavaco Silva government, by Decree-Law 124/92, mainland Portugal officially changed its time zone from WET () to CET ().<ref name="Decree-Law 124/92"> Decree-Law 124/92, 2 July 1992 (in Portuguese). Retrieved 12 May 2013.</ref> Differently from the 1966 move to CET, this time DST was to be observed, as CEST (), from the last Sunday in March to the last Sunday in September. The measure, approved without the consultation of Lisbon Observatory, had the intention of promoting energy savings, in order that “Portugal follow, in work schedules, the countries with which it maintains more frequent contacts” (DL 124/92) and so promoting economic