what was unified during this mentioned period?
Hideyoshi sought to secure his position by rearranging the holdings of the "daimyōs" to his advantage.
Unification
Hideyoshi sought to secure his position by rearranging the holdings of the "daimyōs" to his advantage. 
date of japanese surrender in world war ii September 2, 1945 what were the divisions within their leadership? Suzuki's military-dominated cabinet favored continuing the war. For the Japanese, surrender was unthinkable—Japan had never been successfully invaded or lost a war in its history. Only Mitsumasa Yonai, the Navy minister, was known to desire an early end to the war. why did they surrender then? August 28, 1945 Japanese Instrument of Surrender was signed what happened at hiroshima in this context? United States detonated an atomic bomb over the Japanese city of Hiroshima. and nagasaki? Hours later, the United States dropped a second atomic bomb, this time on the Japanese city of Nagasaki. were there any further surrenders followed after this? It was broadcasted later that Japan was indeed unconditionally surrendering to the allies. which interesting places are there in the former mentioned city? Itsukushima Island, also known as Miyajima how is the weather here? Has a humid subtropical climate characterized by cool to mild winters and hot, humid summers. who used to rule this place during 1589 to 1871? Mōri Terumoto who is this person? He was a Japanese "daimyō". whom did he provide his service to? Toyotomi Hideyoshi is this person another ruler? He is  the "de facto" leader what does this second last term means? It means practices that exist in reality, even though they are not officially recognized by laws. did this mention leader build any castle? Hideyoshi's rule covers most of the Azuchi–Momoyama period of Japan, partially named after his castle, Momoyama Castle. Hideyoshi left an influential and lasting legacy in Japan, including Osaka Castle
He  formalized the balance of power by establishing administrative bodies. These included the Council of Five Elders, who were sworn to keep peace and support the Toyotomi, the five-member Board of House Administrators, who handled routine policy and administrative matters, and the three-member Board of Mediators UNANSWERABLE The Oda clan, Niwa Nagahide and Ikeda Tsuneoki
Azuchi–Momoyama period Azuchi–Momoyama period
Unification Hideyoshi completes the unification
 formalize the balance of power by establishing administrative bodies. These included the Council of Five Elders, who were sworn to keep peace and support the Toyotomi, the five-member Board of House Administrators, who handled routine policy and administrative matters, and the three-member Board of Mediators, who were charged with keeping peace between the first two boards. Although a commoner who had risen through the ranks from foot soldier, Hideyoshi was now in position to challenge even the most senior of the Oda clan's hereditary retainers, and proposed that Nobutada's infant son, Sanpōshi (who became Oda Hidenobu), be named heir rather than Nobunaga's adult third son, Nobutaka, whose cause had been championed by Shibata Katsuie. Having gained the support of other senior retainers, including Niwa Nagahide and Ikeda Tsuneoki, Sanpōshi was named heir and Hideyoshi appointed co-guardian. 
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Azuchi–Momoyama period [SEP] Unification
Hideyoshi sought to secure his position by rearranging the holdings of the "daimyōs" to his advantage. In particular, he reassigned the Tokugawa family to the Kanto region, far from the capital, and surrounded their new territory with more trusted vassals. He also adopted a hostage system, in which the wives and heirs of "daimyōs" resided at his castle town in Osaka. Hideyoshi attempted to provide for an orderly succession by taking the title "taikō", or "retired Kanpaku (Imperial regent)", in 1591, and turned the regency over to his nephew and adopted son Toyotomi Hidetsugu. Only later did he attempt to formalize the balance of power by establishing administrative bodies.