I'd never heard of this 1975 show either. However, the internets have come through for me again. You see, this is an historical show about a monk called Ikkyu-san. Here, lets see what the web has to say about him:
Ikkyu-san (a Buddhist monk and poet who lived from 1394 to 1481) is best remembered for his wit while still a boy. For example, one day he was taken to the castle of a celebrated wit, who said he could not sleep at night for fear of a tiger and asked Ikkyu to help him. There was a large screen with a tiger painted on it in the room, and everyone was laughing at the joke, but Ikkyu san played it straight, asking for rope, which he tied into a noose. Everyone was laughing even harder as it seemed that Ikkyu-san had not caught on to the joke.
Then he dashed out into the garden and shouted, “OK! I'm ready! You chase the tiger into the garden and I'll catch him!”
Ikkyu – Wikipedia, the free encyclopedia:
Ikkyu is one of the most significant (and eccentric) figures in Zen history. To Japanese children, he is a folk hero, mischievous and always out-smarting his teachers and shogun. This is due to the very popular animated TV series “Ikkyu-san”. In Rinzai Zen tradition, he is both heretic and saint. Ikkyu was among the few Zen priests who argued that his enlightenment was deepened by consorting with pavilion girls. He entered brothels wearing his black robes, since for him sexual intercourse was a religious rite. At the same time he warned Zen against its own bureaucratic politicising.
The anime is about Ikkyu as a child, obviously due to him being celebrated as a wit during that time.
The OP movie on Youtube does not allow imbedding – so click this link to watch it.
Instead look at some strangely dressed weirdos dancing to it's theme tune…