I know puppet Shoguns and kidnapping or usurping Shoguns were a key part of the Sengoku Jidai for different Daimyo to grab for power, but was anything happening with the Emperors? I can imagine if a Daimyo somehow managed to convince the Emperor to endorse them it would give them even more legitimacy than the Shogun, and during the Meiji Restoration the Emperor successfully wrested control of the government from the Shogunate. Were the Emperor's strictly apolitical during this time period, did they have opinions on the respective Oda, Toyotomi, or Tokugawa Shoguns, or any preference on the outcome of the climactic Battle of Sekigahara?
I think it's important to first recognise how the feudal system functioned. A lot of people seem to think the emperor is this high-above entity, safe from the mortal conflicts. However, the emperor himself and his court operated the same way as a feudal lord did - sustaining themselves through land. The imperial land across Japan (land specifically reserved for the imperial court) being occupied was a thing that happened long before the Sengoku period, and the emperor himself was extremely poor throughout the this time. A lot of people might point to political donations - surely the emperor can live pretty well-off from daimyos asking him for legitimacy, right? While political donations to the emperor was a thing, not everyone did it. This was also not a steady income, and you never know when the next grant will be sent.
This is why the imperial court was so cooperative with Oda Nobunaga. They weren't equal allies, but their livelihood depended on Nobunaga's funds. This is why when Nobunaga asked the imperial court to mediate a ceasefire with the Asakura-Azai alliance, the imperial court bent over backwards at his request. The Kampaku himself went to Asakura Yoshikage to negotiate, threatening to resign if Yoshikage won't agree. The emperor himself went to Enryaku-ji to ask his brother to stop fighting. To get the emperor to go do your biddings is like getting the Pope to do stuff for you, and I think it shows their desperation more than anything. They knew if they couldn't do stuff for Nobunaga, the fund would stop coming. Just to show it at an easier to understand scale: Toyotomi Hideyoshi bought the right to be adopted by Konoe Sakihisa with 1,000 koku. That was it. Even small kokujins around Japan probably had something similar to this amount. This was all it took for a peasant to be elevated to be of imperial court status (higher than samurais).
The emperor and his court weren't idle, they were trying to scrap by.
Source (idk if it's ok to list sources not in English):
- 明智光秀與本能寺之變: 日本史上最大的謎團和逆轉劇
- 日本戰國．織豐時代史