Nader Shah’s attempt at reconciling

Shi'ism and Sunnism, all I have read was that he attempted to do this for political reasons (if he ousted the Ottomans and the merging of their empire would be made easier), but this went down badly with Shi'ite Iran which had been largely converted to Shi'ism by his Safavid predecessors.

Does anyone have more information on this?

Actually his ethnic origin is not 100% clear, as a child he was kidnapped by Uzbeks as a slave from Khorassan, he escaped and joined the Afshar tribe.

reconcile, I mean that he wanted to settle the differences between sunni and shia and then unite them so that he could absorb the Ottoman Empire with ease (culturally).

Nader Shah was a Turkmen, just like the rest of Turkmens. Nadir Kuli Beg was born in Khorasan, which is a region still full of Turkmens. Uzbegs kidnapped him because his father was dead. And Afshars are a Turkmen tribe.

Absorb Ottoman Empire culturally? That is not only nonsense, but funny. Ottomans werent only 400 tents of Turkmens conquering everywhere they reach. Ottoman Empire was a unique civilization of its own. If it somehow could unite with the Safavid Empire, Persians would become just a subject of the multiethnical Empire, such as Albanians or Armenians.

All I know is that suspicion from him that people wanted to kill him were high.  He taxed heavily the population and killed dissenters, even blinded his son.  His motives might have been genuine, but his tactics seem to backfire on him when finally his own Turkemn Qezelbaash behead him. 

I am not. Expressing my idea shouldnt be judged so. But I really found it funny, what could I say?

No doubt Nadir Shah was a Great leader for his Empire and Iranians. He was the most obvious hero figure in recent Iranian history. He was a fine conquerer and leader. But absorbing Ottoman Empire, is like Canada absorbing USA. I said if the empires united, Persians would become just a subject like Armenians, Albanians, Turkmens etc. What kind of offensive element could you get from such sentence?

Religious reconciliation was a dream in my opinion. How much Shias did Safavid Empire had? I bet it wasnt even over the number of Orthodox subject Ottoman Empire had. So simply, Shia Iranians would become a religious millet in the empire's system, rather than uniting two sects.