The Ottoman–Persian War (1821–1823) ended with the signing of the First Treaty of Erzurum, which re-affirmed the 1639 Zuhab border.[11][12][3] A boundary commission involving Iranian, Ottoman, Russian and British officials assisted with the boundary delimitation, resulting in the Second Treaty of Erzurum of 1847 which affirmed the 1639 border with some small modifications.[13][9] The four-way boundary commission resumed its work in the following years, and after much work and cartographic disputation a detailed map was produced in 1869.[9] Some small modification were made in the vicinity of Qotur as a result of the Treaty of Berlin (1878).[9]