Ub Iwerks was a hugely important figure in the history of cartoons-- and much of it because he and Walt Disney created some amazingly successful characters, such as Mickey Mouse. However, in 1930 Ub went out on his own and started his own studio...with less than stellar results. The animation quality was generally good but the stories were very bland...and often hampered by cutesy characters and singing. There's a tiny bit of this in "The Valiant Tailor" but fortunately the singing is very limited and the artwork a step above Iwerks' usual.
When the story begins, I found myself marveling at the use of a multipane to create a wonderful sense of 3-D. The Fleischer Brothers managed to make great use of it in some of their cartoons and Iwerks' attempt is almost as good as theirs. As for the rest of the animation, it's also quite good. As for the story, a jerk giant is in the kingdom and is intent on killing the King. But the King is angry at the tailor....and is there any way this simple man can get back on the King's good graces?
The cartoon is pleasant and looks nice. However, it's not particularly funny or engaging....and when you think of how Disney handled the same material in "Brave Little Tailor" you realize how ordinary the Iwerks film actually is.