I am not a specialist of eastern Chrsitians, but I can make a resume of the paper written by a specialist of this population :
1/ the heart of Nestorianism was in Mesopotamia but many missionaries spred this religion until Central Asia. For that reason, Mongols were friendly with them when they arrived in the ME.
But at the 14th century Tamerlan (who was not Mongol but Turk) destroyed a great aprt of Iran and Mespotamia. Like many populations (Kurds and others) Christians fled in moutains, along the Tigris and the Zab river, around Hakkari. During centuries, some other groups reached Urmiah, or went to the Western parto of Mosul.
According the author the "heart" of these Nestorians was in Hakkari, where sieged the Patriarch of Assyrian church, in Qotchanès. The "Chaldea" Patriarch was in Mosul (it was after the scission of these Chrsitians).
Many catholic and Protestants missions tried to incorporate these Christians in their own churches. So we have reaports of American evangelists, for example, on this population aroun 1835-40. They described them like very mobile people, traveling from Zagros to Azerbaydlan and Caucasus. The main reason of this mobility was 1/ economical motives, most poor people were jobless because of the aghas' power. When recolts were bad, for example, most of peasants were without mean to survive. So they left their land to Caucasus, where Russia need workers to modernize its regions (roads, trains, buildings, etc). Some other Christians went to Mosul and mesopotamia, becoming workers in archeological excavations. From Azerbaydjan, poor Assyrians went to Tiflis (Georgia) where they exercsed many jobs like Water-carriers, painters, masons... In Caucasus they built the railways and worked in oilfield of Baku. Much of them settled definitively in Azerbaydjan.
Russia had a policy to expell muslims and calling Christians on its border lands. For example if an Assyrian of Persia came to Russia, he received some fields and was exempted to pay taxes during 6 years. it was the same thing from Ottoman Assyrians who came to samavat in the district of Kars.At the beginning of the 20th cenrury, there was more than 2000 Assyrians in Tiflis. So Caucasus was, during the 19th century the first place of migration for Assyrians.
The second reason was the politcal unstability in Ottoman/Qadjar Kurdistan, when both sultan tried to reduce the power and the independance of Kurdish tribes. Constant wars and military occupation obliged farmer to lave their villages. At this time, there were Kurdish/Assyrian confederations of nomads, for the Assyrian tribes of Hakkari were, like Kurds, constituted by rich aghas oprressing the rayas (peasnats)... At this period, it was more a question of social classes (rich nomades vs poor sendentaries rayas) than a problem of religion or nations. Kurdish princes and the Nestorian Patriarch were quite independant against Ottoman administration.
I resume : Kurdish princes faced violently Ottoman army, and the Nestorian Patriarch (Mar Shimun tried to seek a foreign alliance (hopiong mostly in Russian or Western support).
The massacres of Chrsitians of 1895 incited more and more Assyrians to migrate in Iran between 1896 to 1914.
During the WWI, Urmiah was occupied by Russians who tried to make alliance with Assyrians, and then, when Kurds and Turks seized Urmiah, most Christians fled in Caucasus. In 1915, Mar Shimun made his main mistake : he stated openly that he supported Russians, and entered in war with Ottomans. Then Assyrian tribes were attacked by Kurdish tribes and Ottoman troops,
without receiving any kind of military helps from Russians.
The Revolution of 1917 was a tragedy for Assyrians, for Russia stopped the war and Assyrians were abandonned to England, which promised to Armenians and Assyrians their independance... but let them. So the genocide happened. Assyrians from Hakakri fled in Iraq. In spite of the promise to have their own state (like Armenia/Kurdistan in the Treaty of Sèvres) they were forget by the League of Nation, who tried to make agreement with other populations of Northern Iraq to let them settle in these areas (I have red the reaports of debates in the League concerning the resettlement of Assyrians).
Assyrians hoped to come backin Hakkari, they couldnot. They hoped to have a state, they had not. After Brittons left iraq there were another massacres (in 1933, for example). Then a part of them fled in Eastern Syria. Nomadic Assyrian tribes were obliged to become sedentary people, and Assyrians were spred, from Caucasus to Syria.
That is all for the narration of "Assyrian wandering".
Could someone give me the names of Kurdish Tribes who are settled in Hakkari??
Ertus,î, Jirkî, Dirî, Pinyanis,î, Oramarî, Dorskî.
For pictures, well if you ask "Hakkari" in gogle images you will have a lot.