Is this a run-on sentence?:

Feudalistic Japan and Europe, followed and were based upon similar ideals, and were formed in the hierarchy; bonds tying individuals together in a descending order: Nobles, warriors to tenants.

That makes sense. Thanks again.

It is hard to make sense out of it because of the very strange uses of punctuation.

Feudalistic Japan and Europe followed and were based upon similar ideals and were formed in the hierarchy
~ If this is intended to be one sentence, then are you saying that Japan and European countries in feudal times were similar in many ways?
~ I think you mean "ideas" not "ideals." Please look up those two words and learn the difference so you don't confuse them again.
~ I have no idea what the last part means: "and were formed in the hierarchy." Please explain.

bonds tying individuals together in a descending order: Nobles, warriors to tenants.
This part is not a sentence — it's a fragment. The colon is used correctly, though, and so is the period at the end.

I hope you'll rewrite this so it makes sense.

Thank you. I meant they were based upon a hierarchy.

How would you re-create that sentence so it makes sense? Thank you.

OK.

One thing about using semicolons is that you need equal things (usually clauses) before and after. For example, if you have two independent clauses you want to make into a compound sentence, you can use a semicolon after the first clause and a period at the end of the second clause. There are other, trickier uses for the semicolon, but this is the most common — making a compound sentence.

Be sure to post your revision if you want it checked over.

The feudalistic hierarchies of Japan and Europe were based upon similar ideas, a main one being the obedience bond, tying individuals together in a descending order: Nobles, to warriors, to tenants.

That sounds better. Thanks so much for your help!

The hierarchies of feudal Japan and the countries in feudal Europe were based upon similar ideas, a main one being the obedience bond, tying individuals together in a descending order: Nobles, to warriors, to tenants.

I made a couple of changes. Your comparison needs to be clear — countries to countries, not country (Japan) to continent (Europe). The rest is fine.

Oh, sorry — in my last reply, I combined yours and mine!!

You're very welcome!