Four non English prog bands from the 70's.........

They are often just as reliable as this site. 

Anyway, it turns out Chicago are jazz rock/fusion on here so if I include them I also have to include all the other jazz rock/fusion bands including the ones that were mentioned already. 

I don't think any of their albums charted in the US though and that song is rather disco sounding. May as well suggest ABBA. :P  Actually I wish I could include them since I like Kayak quite a bit.

I think that was me haha. Thanks for giving my point some credit. Though I think your view on it is valid as well.

As for Chicago, I would take a listen to get a better sense of them, particularly the first five albums (well, the fourth is a triple live album, but it's between III and V, so they consider it four I guess). These ones have the most amount of prog moments. And yes, I mean Prog, with multi-track suites, extended fusion solos, and some modernist classical compositional techniques, almost Zappa-esque (particularly II and III). VI is ok, shows where they were going, which was more commercial territory; the first disc of VII is very fusion-oriented, while the second disc is more like VI. After that, they kind of lost the prog until maybe their comeback with XX. If we could ascribe multiple genres here on PA, I'd say Chicago's first five albums live right in the sweet spot between Crossover and Fusion.

They were incredibly popular in the States and elsewhere, and if you can include Kansas, who are also mostly beloved on this site for their first five albums, I could see Chicago on that list. However, they certainly are not as influential in the prog realm as the four you have listed, so I could understand not including them. Especially if you're being strict on the fusion exclusion (that's a catchy phrase, "fusion exclusion" heh).

Unfortunately not everyone agrees with that. I remember telling my brother I thought Chicago were prog and he has seen them in concert and told me that nothing he heard sounded like prog. Maybe they cut the prog stuff from their set I don't know. Someone on here got on my case because I didn't make a distinction between prog and progressive rock. A band like Chicago is a good case for his point though. They were progressive rock but I have a hard time thinking of them as prog. Ultimately I will pass since I don't consider Chicago to be a prog band. They are kind of the same as Journey in that they started in that direction but ultimately became something different. 

Anyway, according to wikipedia only the first two and the seventh one are progressive rock and even those have other categories as well. They are crossover on here though.

Imo, Journey are on the bubble like Styx. Styx are crossover prog on here but Journey are only prog related. The early Journey albums were very proggish at least. A bit jazz rockish also.

From wikipedia: " It was also moderately successful in America, where it reached number 154 on the Billboard Top LPs & Tapes chart.^[7] ." 

I know Styx had prog or proggy tracks back then but I had a hard time justifying their inclusion so I figured I would leave them off. 

I see that Ambrosia's first album charted so there's at least one already that I missed. However, that could be more art rockish also imo. 

........to break through commercially in the US in the 70's. 

1. Focus

2. PFM

3. Kansas

4. Rush

All four charted in the US (yes even PFM believe it or not).

Some people might say Nektar(who also charted but they were English so I don't really count them). Some might say Triumvirat but I don't think they had any real chart success in the US. Also, Eloy didn't break through in America and neither did Banco. Tangerine Dream might have but they were more electronic and probably not really considered progressive rock at the time. Also, I don't really count Styx since they were closer to art rock/pomp rock or even arena rock.

I would be curious to know if there any from the 80's or 90's(or even later)but I doubt it.