The Demeo crew were involved in drug business with the Cubans in the late 70s. We also know that Rosenberg got killed because of he killing few Cuban guys. Who are those Cubans?

I think it was some guys that were connected to a bunch of columbians. The people rosenberg killed one was the actual cuban dealer, the other the dealers cousin and his columbian connects girlfriend.

The columbians sent a hit squad down to new york to air out a few social clubs or do a few trademark mass murders of some mob guys and their families i guess if rosenberg wasnt killed.

Rosenberg was doing a little drugs deal on the side without Roys knowledge, he roped in Joey and Anthony and thought - "why pay for the drugs when I can just kill them and take them for free".
He may have got away with it if he hadnt used the alias "Chris DeMeo".
This was traced back to Roy (obviously) and as Chris was his guy he had to sort it out.
The Gambino's werent gonna allow Roy to start a war for someone as lowly as Chris Rosenberg and so Nino ordered Roy to whack Chris and be done with it

Interesting information. i mean Demeo made a wise choice. Not a good idea to mess with these Cubans/Columbians these guys come in numbers. Hard to figure what cartel these guys are working in, but I guess they are prety brutal. It always remind me of the movie Scarface at the end scene, when these guys were over dozen men.

One of the cubans was a member of a o.c. group in Florida and was nicknamed "El Negro".So maybe this was the guy that used to work for Griselda Blanco as a hitman named Carlos Vanegas “El Negro”,since this was in the late 70's.The ones that got killed were William Serrano,Charles Padnick and his son.

wasnt el negro featured in cocaine cowboys.

Padnick was Roy's friend.Padnick's son's name was Jamie.Roy even took his wife to Jamie's Bar Mitzvah.

This situation really epitomized what a greedy,blood-thirsty,strunzo Harvey "Chris Rosalia/DeMeo" Rosenberg was.Charles Padnick owned an auto body shop in Brooklyn at one time.When his business started to fail,he borrowed money from Roy.He tried to start anew in Florida,but that business was also failing and he borrowed even more money from others,just to keep up on his payments to Roy.Padnick had known Harvey since he was a young boy,having vacationed at the same resort in the Catskills as Harvey's parents.One of the Padnick's employees had access to large quantities of high quality cocaine for a good price.The cash-strapped Padnicks decided to become amateur drug dealers,thinking that a couple big,quick scores would be the answer to all of their business and money woes.How wrong they were !!!

They arranged a one kilo deal with Harvey who shortly thereafter informed them that he'd like to do another deal,but this time for 12 kilos.The Padnicks must've thought this was the next best thing to hitting the lottery.Little did they know,while Harvey certainly wanted the 12 kilos,he never had any intention of paying for them,so he ended up killing the Padnicks and 2 representatives of the actual supplier,who just so happened to be the supplier's girlfriend and his cousin.Though arrogant,Harvey was also self-loathing and made the colossal mistake of billing himself as "Chris DeMeo".That blunder is what led directly to his much deserved demise.

If Harvey wasn't a millionaire already at this point in his life,he was surely well on his way.By any stretch of the imagination,he wasn't even close to hurting for cash.Now,he was about to aquire high quality stuff for a very good price and would've easily quintupled his initial investment by the most conservative of estimates.Making 5x your money wasn't good enough for the parsimonious,feral savage though,and in the end,he ended up getting whacked over it.It's too bad it didn't happen sooner.