Krestos and Walda Haymanot sent sealed letters to various countries to announce the death of Yohannes I, and that the reign of his son Iyasu I has begun. Administrative reforms His reign is noteworthy for the attention he devoted to administration, holding a large number of councils to settle theological and ecclesiastical matters (the first in 1684, in the public square of Gondar), matters of state, and to proclaim laws. In the late 17th century, Iyasu I established the Lewa; the first separate armed force with police functions. Its duties were to keep public order in the towns and on the roads. In 1698, after reports of extortion suffered by merchants, Iyasu I reasserted his control over the growing lawlessness in the Tigray province. In November, Iyasu I summoned the chiefs of Tigray, and interrogated them on the taxes then exacted at the customs posts (also known as the Kella system). This led to decrease of taxes, and tax exemptions for small merchantsm, which encouraged trade. The monarch declared that anyone attempting to tax them woud have his property confiscated, and be punishable by death. Iyasu I ordered the chiefs, and the location of all Tigray Kella, be announced by herald, and recorded in the royal chronicle. Military campaigns and conflicts Alliances Iyasu I strengthen his control over his southern domains through his alliance with two influential Amhara warlords, Demetros of Merhabete and Negasi of Menz. Having accepted the suzerainty of their northern monarch, Demetros was granted the old imperial title of Sahafe Lam while Negasi was honoured in Gondar with pomp and circumstance receiving gifts from the Emperor. It was during his reign that individual Oromo first found service in the Imperial court. In 1704, Iyasu I settled various Oromo groups who accepted Amhara culture, adopted the Amharic language, and converted to Christianity such as the Gawe on the north bank of the Abbay as a bulwark against attacks by other hostile Oromos living south of the Abbay. Several ethnic groups suffering from persecution and raids in Oromo occupied territories, from the Kordidas Amharas in 1681 to the Talatas in 1695, aligned themselves with Iyasu's government, in hope of securing succour from the monarch. In 1689, Iyasu's Armenian trade agent, Khodja Murad told the Dutch in Batavia that the king of Hadiya had ‘‘submitted of his own free will to the rule of Abyssinia.’’ after suffering defeats and pressures