It’s making me so angry

Well I would see 2 sides of the coin.

As a foreigner with an English partner I actually face very difficult position from my end. My partners family don’t quite understand our baby is mixed and push everything British.

Sadly if you choose a foreign partner it’s to be expected the child will speak 2 languages and will have something from both cultures. That said if you live in England they will be more exposed to English language and culture anyway but speaking another language is great for development and perhaps even future employment opportunities etc.

If I were in your shoes which I kind of was I’d try to find a compromise. There will be time to learn both cultures (we will be going to my country of origin every 2 years for Christmas and other celebrations)
I understand you are more concerned about respect from the family which is up to your partner to set and stand up for you but you also can’t expect a fully English child if you chose a foreigner as a spouse

You chose a Polish partner. Them calling your child the wrong name upsetfing you is torally valid. They should use the name you chose. And saying they will MAKE them polish os kinda weird. But you have to expect your child to be both English AND Polish because they are. He's going to want to connect with his Polish family and youre kind of preventing that. He should be bilingual, thats not a bad thing. And although its kinda rude for them to speak Polish around you so tou purposely dont understand, its also rude of you to expect them to only speak English. Why havent you learnt Polish so you can connect with them? Youre relationship would probably be better for it

My brother is the one whose with a Polish woman. None of her family speak English or it’s very little hence one of the reasons he doesn’t overly like going over to visit. On the plus side when they have arguments he can just sit back and relax. However he should also make the effort to learn the language as well. He’s just as bad as he’ll call his nephew Dameon and they have no idea of the pop culture reference. There is also a lot of cultural differences. I would however embrace your son learning Polish and learning about his routes. I don’t see anything wrong with him having presents that will help him learn as long as the focus is on him enjoying it.

Whilst it’s pretty rude for your partner’s family to only talk in Polish around you knowing you don’t speak the language, I’m not seeing how the other stuff is bad.

Your child is British and Polish; two difference ethnicities and national identities. They have the amazing wealth of two nationalities, two languages, two cultures. Why don’t you want that? Surely it’s nice for your Polish partner to see baby embracing his family’s cultures and languages and knowing their heritage. Do you not want baby speaking Polish too? My bf is Italian and half her family talked in Italian to her and half in English, being bilingual as a child is amazing for development!

My husband isn’t English and his family always buy gifts from home, try to get the kids into their culture, push sports on them, make jokes about them being half English. That’s half of their life and culture and it’s 100% understandable when you get a partner who isn’t from England. Our children are only 50% us.