1916年，Iyasu被废，并逃离埃塞俄比亚。尽管有一些关于Tafari参与政变的问题，但在这些事件之后，Iyasu的姨妈Zewditu（Menelik II的女儿）登上了王位。塔法里被提升到拉斯等级（相当于杜克），并成为皇太子。此外，Zewditu将他命名为她的继承人和摄政王，并承诺她将成为他的忠告的统治者。 Ras Tafari维持该国的日常行政任务，并致力于埃塞俄比亚的现代化，就像Menelik II所做的那样。 1923年，他承诺结束奴隶制，从而确保埃塞俄比亚加入国际联盟（注意到，奴隶制在该国持续到20世纪30年代）。在接下来的几年里，塔法里在中东和欧洲进行了广泛的巡视，从事外交工作。尽管他认识到需要欧洲盟国，但他对与他们密切合作持谨慎态度，并强调埃塞俄比亚需要经济独立。在此期间，他加强了对埃塞俄比亚许多省份的控制，1928年，当他的权威遭到西达摩省省长巴尔查萨福的挑战时，事情发生了变化。 Zewditu女士支持萨福，并指责Tafari叛国，部分原因是他与意大利政府签署了一项和平条约。在皇后宫殿发生政变之后，她心软了，宣布塔法里为王。在纸面上，Tafari和Zewditu一起统治，这在埃塞俄比亚从未发生过。 1930年，Zewditu的丈夫Ras Gugsa Welle领导了反对Tafari的起义。他被杀了，不久之后，女皇自己就去世了;有传言说她中毒，但现代学者认为她实际上死于糖尿病的并发症。
In 1916, Iyasu was abandoned and fled Ethiopia. Despite some questions about Tafari’s participation in the coup, after these incidents, Iyasu’s aunt Zewditu (the daughter of Menelik II) took the throne. Tafari was promoted to the Lass rank (equivalent to Duke) and became the Crown Prince. In addition, Zewditu named him her heir and the Regent, and promised that she would become the ruler of his advice. Ras Tafari maintains the day-to-day administrative tasks of the country and is committed to the modernization of Ethiopia, as Menelik II did. In 1923, he pledged to end slavery, thereby ensuring Ethiopia’s accession to the League of Nations (note that slavery continued in the country until the 1930s). In the next few years, Tafari conducted extensive inspections in the Middle East and Europe and engaged in diplomatic work. Although he recognizes the need for European allies, he is cautious about working closely with them and stresses that Ethiopia needs economic independence. During this time, he strengthened his control over many provinces in Ethiopia, and things changed in 1928 when his authority was challenged by the Governor of West Dharma, Balchasaf. Ms. Zewditu supported Sappho and accused Tafari of treason, in part because he signed a peace treaty with the Italian government. After a coup in the Queen’s Palace, she was soft and declared Tafari to be king. On paper, Tafari and Zewditu rule together, which has never happened in Ethiopia. In 1930, Zewditu’s husband, Ras Gugsa Welle, led an uprising against Tafari. He was killed, and soon after, the Queen died on her own; there were rumors that she was poisoned, but modern scholars thought she actually died of complications of diabetes.