They’re thoroughly conflated in the UK, people use both ‘Gypsy’ and ‘Traveller’ (and a selection of assorted slurs) to refer to a whole range of traditionally travelling groups. Some people seem to think that ‘travellers’ is the polite form of Gypsy and ‘Roma’ is uncommon enough that my spellcheck just flagged it up.
Re: Black people in Ontario…
Growing up in what was then small-town Whitby, I never saw a Black person until grade six. I was in the hospital for an eye operation and my eyes were bandaged for a week. I recognized the nurse by her voice. Then, one evening, they gently unwrapped my eyes in a darkened room, and I could see the lights out the window. I could also see our nurse, and to my surprise she was Black. I had never heard her accent before, and I had thought she was old…
Later, in grade seven, we had a science teacher, Mr Hanson, who was Black. He was the first Black person I interacted with regularly.
Later, in high school, things started to open out and I started to meet various Black, Asian, Indian, etc students. This was the late seventies.
I was heckled while speaking English in Montréal; they shut up when my friends and I resumed speaking in Esperanto. 
Yes. The Travellers are Irish in origin, and their language, Shelta, appears to have Gaelic roots with heavy English influence.
The Roma speak an Indo-Aryan language and are believed to have originated in northern India.
Yes, people don’t realize how isolated Newfoundland was at the time. The US bases established there during WWII, some of which were maintained for years afterwards, were the only places you might see a black person.
My mother is from Newfoundland, and there’s a family story about the first time one of my uncles saw a black person, when he was very young, and saw a US soldier while travelling with my grandfather. “Daddy, don’t that man never wash his face?!?” is what he was reported to have said.
ETA: I’m pretty sure it was near this base: Ernest Harmon Air Force Base - Wikipedia
For what it’s worth, the individual who posted about what it was like to spend some time in Canada is a woman, not a man.
Rest assured that racism against blacks is alive and well among the Chinese Canadian community. For instance, my wife and I went on a bus tour from Toronto to Chicago and, regarding one of the motels we stayed at, a gentleman commented that he slept on his bed fully clothed because he thought black people had been staying in that room.
With regards to slavery, my impression is that black Canadians in English Canada are often of Caribbean origin and in French Canada are often from former French colonies in Africa.
The largest French speaking black demographic in Canada is actually Haitian. Some parts of the Caribbean are former or current French colonies (the aforementioned Haiti, Guadeloupe, Martinique, etc).
Obviously there are racists everywhere, and there are non-racists everywhere. There’s no doubt in my mind that statistically though Canada is more tolerant than the US to racism.
As mentioned, part of this is probably due to the fact that until fairly recently there weren’t a lot of visible minorities in Canada. My grade school pictures show a bunch of whiteys, and that’s it. I don’t recall any black people in high school, and very, very few in college.
I don’t believe things have changed much in small town or rural Canada, although large cities are quite cosmopolitan now.
Also, we’re a young country (151 years old) and there’s more a sense that “we’re all from somewhere.”
As a brown skin Canadian who’s also lived in several other countries I know a thing or 200 about racism. Are there individual racists here or in other countries? Yes of course. Are these racists found only in some ethnicities or demographics? Of course not. Every culture, every ethnicity has its share of doctors and thieves, tolerant persons and racists. Sure, there may be more racists in some demographics than others, but you can’t point at one racist individual from ethnicity X and say all X are racists, that’ll be racist in itself, lol.
Here in Canada, I’ve experienced plenty of mild racism from individuals, but I’ve never been denied service, the quality of service can range from bad to exceptional like for any other Canadian, and during my career I’ve always been paid higher than average, never felt a glass ceiling. In some European countries, I have very occasionally been denied service, but again the average person is quite tolerant. The big difference is that here, we’re multi-cultural, i.e. a “black” man can be part of a Lion Dance troop, a “Chinese” man can be part of a Mariachi band, or a “white” woman can become a belly dancer, no problem. I myself have participated in many cultural events from Chinese to Celtic and I’ve always been welcomed.
I was the first in my high school, things changed very quickly over the past four decades. There was a slump in acceptance during the Harper years but Trudeau has brought back a big sense of multi-culturasim and tolerance. I’m asked less and less often that dreaded question “where are you from?”
I’ve lived in small towns and rural areas. There are most definitely plenty of “visible minorities” there and nobody seemed to care about my skin color, or anybody else’s. But again it’s down to the individual, if someone goes to a Canadian small town expecting to see only blue-eyed blonds, that’s all they will see. In a big city it’s easy to see the diversity because people are more concentrated, in a small town people are spread out so the diversity is not as noticeable, but it’s still there.
And another depressing episode, this time from Toronto: Arrest after heated exchange at Toronto ferry terminal