More Isshin! Why is it always him?

I'M NOT DEAD!

Well, technically, I am. But that's another story altogether. And it has nothing to do with today's blog post, which is:

Which Squad Was Isshin Captain Of?

After extensive (obsessive) research, I have come up with the following information.

Given the fact that Isshin only lost his powers 20 years ago, according to Urahara, it's safe to assume that was when he left Soul Society. In which case, his squad must have gotten a new captain fairly recently. Therefore:

1st squad: impossible. Yamamoto-soutaichou has been that captain for more than 2000 years.

2nd squad: highly unlikely. Yoruichi was captain until she left 100 years ago, and it's fairly safe to assume that Soi Fon took up the mantle of captain directly after she left.

3rd squad: possible. Rose was captain until he became Visored, and Ichimaru only took the position around 50 years ago. There's a 50 year gap. But unless Isshin kept his powers until he met Masaki, this would be 30 years too soon.

4th squad: impossible. Unohana-taichou has held that position for more than 200 years, probably longer.

5th squad: unlikely. After Hirako left, it's safe to assume that his lieutenant, Aizen, became the next captain.

6th squad: Highly unlikely. Ginrei-dono was the previous captain, and Nii-sama became captain about 50 years ago. It's probable that Ginrei-dono passed it directly to him.

7th squad: possible. Love became a Visored, and we don't know when Komamura took his place. But I'm guessing that he became a captain along with Tousen, given their history.

8th squad: impossible. Kyouraku has been captain for 1000 years.

9th squad: unlikely. When Kensei became Visored, it's likely his highest remaining subordinate, Tousen, became the next captain.

10th squad: likely. The previous captain, before Turn Back The Pendulum, was killed mysteriously, and Hitsugaya-taichou didn't even begin at the Academy until 45 years ago. This is my choice for Isshin's captaincy.

11th squad: unlikely. Zaraki-taichou was probably the Kenpachi they were talking about in the Pendulum, as Yoruichi recognizes his reiatsu in the Soul Society arc. Also, Ikkaku didn't become a shinigami until Ken-chan did, and he recognizes Urahara as a captain in the Soul Society arc. (Note: in the Bount arc, Tousen is wearing a haori when Ken-chan kills the previous Kenpachi, indicating that his captaincy came at some time after the Pendulum. I am dismissing this as merely a filler discrepancy until we see otherwise.)

12th squad: probably impossible. As far as we can tell, Kurotsuchi-taichou took the position directly after Urahara was banished.

13th squad: impossible. This has been Ukitake-taichou's post for the past 1000 years.

...

And now we see the depth of my obsession...

I may update this as we get new information, but for now, my guess is that Isshin was the captain of 10th squad until recently, and when he left Hitsugaya-taichou took his place.

Now, my next question: when will I get a life?