Just caught up with Sengoku BASARA: The Last Party and it was a fun watch despite not making much sense at certain parts. Sengoku BASARA's charm really rests in its spirit of never taking itself too seriously and the unabashedly ridiculous spin on Sengoku history and character heroics. That said, the main draw of the anime for me lies in Masamune and Kojuurou, two characters who sometimes share moments that seem to belong to a more serious historical anime than the over-the-top fun that is Sengoku BASARA. Masamune's recollection of Kojuurou's words and actions in the second season surprised me a little in that I found it genuinely touching. There's definitely an unspoken bond between the two if not affection. Thinking about it, the quieter moments between Masamune and Kojuurou balance nicely against the extremely dramatic antics of Yukimura and Shingen, which I enjoy as well. After two seasons, I still find their "YUKIMURA!!!! OYAKATA-SAMA!!!!" shouting-fighting contest absolutely hilarious.

I saw a bit of Kagetora and Naoe in Masamune and Kojuurou when I first started watching Sengoku BASARA, much to my amusement. Initially I thought I was just projecting too much... but then I was doubly amused when I realized later that Kuwabara-sensei had actually made this comparison in Mirage of Blaze. Somewhere in either the third or fourth volume, Takaya was reminded of his own relationship with Naoe when he saw the attention that Kojuurou gave to Masamune.

Sengoku BASARA has also increased my interest in the historical Date Masamune. The man turned out to be a more impressive figure than I expected in my research. It's quite telling that both Toyotomi Hideyoshi and Tokugawa Ieyasu were somewhat wary of him due to his power and intellect (and possibly his inscrutable personality) even though he served both of them loyally. In fact, Hideyoshi saw Masamune as a threat to his power and forced him to give up Aizu, a strategic domain worth one million koku which Masamune had acquired by defeating the Ashina. Hideyoshi assigned Masamune to the old Iwatesawa castle (later renamed Iwadeyama) instead although that didn't stop Masamune from developing Iwadeyama into a political and economic center while he was there.

Tokugawa Ieyasu was more generous, giving Masamune the large Sendai domain. Even so, Ieyasu never fully trusted Masamune's allegiance. With the Sendai domain under his control, Masamune became one of the most powerful daimyos in Japan to the extent where many people believed he could usurp Ieyasu's position as the shogun. His finance minister, Suzuki Motonobu, even drafted a constitution for a Date shogunate.

Other fun bits of history I found:

The Date army was so fearless and powerful that they didn't bother to build high walls for their castle.

All members of the Date clan, men and women, were trained in martial arts.

On a side note, fans of the anime should definitely check out the Sengoku BASARA live seiyuu events. They often have a special "Cast Shuffle" segment where they change the voice cast of a particular scene to really hilarious results. I think most of the seiyuu dread being selected to voice Yukimura (for some reason, Hoshi Souichirou is almost never present at these events) and poor Nakapan seems to get picked quite often. The 2009 Sengoku BASARA Festival Spring Event has the funniest "Cast Shuffle" I've seen so far. Nakapan was straining his voice so much for Yukimura that his line delivery was somewhat mangled, but it was a good effort. Ishino Ryuuzou's Yukimura sounded like a bird talking and Fujiwara Keiji's was... I don't even know how to describe it except that Nakahara Shigeru couldn't stop laughing. As for the other characters, Morimori was particularly amazing in his imitation of Takeda Shingen; the similarity was uncanny!