Philip Riteman was just 13 when the Nazis shoved him and his family on to a train bound for Auschwitz from the Pruzhany ghetto in Poland. At the time, he and his family had no idea they were being carted to their deaths.

"Three o'clock in the morning somebody [yells] and I see the German sitting with a gun and screaming, yelling, 'Out, out you Jews!'" Riteman recalled.

They walked to the railroad tracks and Riteman saw freight trains stretching as far as his eyes could see. Riteman, a Polish Jew, said about 100 people were crammed into the trains which measured roughly 8ft by 20ft. The Nazis told them it would be an hour's ride.

"Two hours gone, three hours gone - all day on the train. [On] the train we shake. The train slow, slow, you hear rifle shooting, but you can't see it because you look to the boards. And we stay, all glued together. Could you picture this? Can you imagine? I wouldn't do this to animals."

As the train clicked along the tracks on the seemingly endless ride, a man soon dropped dead at Riteman's feet - the first casualty of this tragic journey.

"A fellow behind me, a tall fellow, he says, 'Maybe you can try shifting, move your feet, maybe one inch, everybody moves an inch, and see if we can put the dead body to the wall.' We did this."

The train continued rolling through the countryside. For what felt like days, a young mother's baby began crying. Its screams still torment Riteman to this day. Then, it stopped.

"The baby died in the mother's arms," said Riteman bitterly. "She was hysterical."

Six or seven days passed. There was no, food, water, or bathrooms.

"I peed every day in my pants. Everybody [defecates] in their pants and pees, and everybody screaming, crying - unbelievable they could do this to human beings."

Then, one morning, they finally arrived at Auschwitz. Riteman was separated from his family, and it was the last time he would ever see them again.

"In the afternoon, my parents already was gassed," he said, with tears in his eyes.

"Trains after trains coming in. They gas them. Could you imagine? I couldn't believe it. I was there a month and I didn't believe they'd do this. I thought I was still going to see my parents. I will still see my sisters, my brothers. Then I found out. I see people going to the crematoriums, and they gassed 5,000, 10,000 at one time. It's very, very hard for me to talk about it."

Riteman's entire family was exterminated by the Nazis. His father, mother, five brothers, two sisters, his grandparents, and nine uncles and aunts were annihilated in Auschwitz.

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'I will never forget'

Riteman was later transferred to Dachau concentration camp. After being liberated by the Americans in 1945, he spent time in a displaced persons camp. He weighed just 34kg.

Then, in 1946, he landed in Newfoundland, then pre-Confederation Canada.

This is just one gruesome snapshot of the Holocaust, which claimed the lives of about six million Jews during World War II. More than a million Jews like Riteman were hauled off to Auschwitz but only a handful made it out alive. At least 960,000 perished there.

According to The Blue Card, an international organisation that provides financial assistance and other resources to Holocaust survivors, there are an estimated 100,000 survivors still alive today, many of whom live in poverty.

April 23 marked Israel's observance of Yom HaShoah, Holocaust Remembrance Day, a day which hangs heavy on the hearts of many survivors around the world.

"I will never forgive, and I will never forget," said Fanny Starr, 95, another Polish Holocaust survivor who endured the terrors of Auschwitz.

Starr, who now lives in Denver, Colorado, lost her mother, two of her siblings, and many other family members to the gas chambers of the German concentration camp. She remembers the atrocities well. Ashes of burnt bodies fell like snow from the Auschwitz crematoriums, she said.

"That was such a heinous crime against humanity to try to annihilate our race," Starr added. "But thank God, they didn't succeed. Six million people lost. People who committed no crime, they killed nobody, without no reason, we were just slaughtered."

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'Stand up to hatred early on'

With the tide of nationalist politics and xenophobia seemingly rising on both sides of the Atlantic, Starr said it's more important today than ever to commemorate the Holocaust so the world can be reminded of what can result when toxic ideologies grip entire countries and continents.

"Something like the Holocaust just doesn't happen overnight," said Ken Jacobson, deputy national director of the Anti-Defamation League in New York.

"It's related to a long history of anti-Semitism in Europe, over 2,000 years, which became deeply embedded in Western civilisation. That's why we commemorate the Holocaust, to symbolise that it just didn't happen, it took a period of evolution for it to happen, and that one has to stand up against hatred early on."

On Tuesday, at the US Capitol in Washington DC, President Donald Trump commemorated Yom HaShoah with a sombre speech.

"Those who deny the Holocaust are accomplice to this horrible evil," Trump said. "We will never, ever be silent in the face of evil again," he added.

Despite Trump's remorseful speech, during and after his presidential campaign, countless synagogues, playgrounds, and public areas were vandalised with graffiti swastikas and phrases like "Heil Trump" and "Make America White Again".

Although Trump has called for hate crimes being carried out in his name to stop, he was slow to denounce support from racist factions across the country, including David Duke, former leader of the Ku Klux Klan, and his populist rhetoric has also coaxed some of the radical right's ideologies to emerge from the shadows.

"Some of the populism, [you could] call it nationalism," described Jacobson. "Some of it's coming from the right again, some is coming from the left. [It's] very disturbing because it has an anti-democratic feel, and it emboldens those people who engage in this invasive, discriminatory, Islamophobic, anti-Semitic behaviour."

According to the Anti-Defamation League, anti-Semitic hate crimes against Jews, including assaults, vandalism, and harassment, rose by 34 percent in 2016. In the early months of 2017, these incidents are continuing to spike.

"We know that 30 million Americans still have anti-Semitic attitudes," Jacobson added. "In the past, because of civil society, because of the mood of the country, very few of them ever would act out those attitudes. Because of the [current] atmosphere, some of it from the campaign, some of it from other kinds of issues as well, a sense of anxiety about the political world, about the economic world, about identity, has come together in a way that's emboldened a certain number of people to now act out their anti-Semitic attitudes in a way that they haven't for quite a while."

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Nationalist political climate

Jews are the most targeted religious group for hate crimes in the US, a phenomenon that was prevalent in American society long before Trump's rise and nationalist politics shifted to the mainstream.

In 2015, Jews were targeted twice as much as Muslims for religiously motivated hate crimes in the US.

The Federal Bureau of Investigation (FBI), which compiles an annual report of hate crimes based on data from nearly 15,000 law enforcement agencies, found that of 5,850 registered hate crimes in 2015, 1,354 were motivated by religious bias. Of those, 51.3 percent - or roughly 694 - of these were anti-Jewish hate crimes.

"I definitely think [Trump's] rhetoric has emboldened people on the radical right," said Heidi Beirich, an researcher and expert on extremism and nativism at the Southern Poverty Law Centre (SPLC) in Montgomery, Alabama.

Beirich told Al Jazeera that the SPLC collected data on about 1,800 hate crime-related incidents in the post-election period. She estimated that about one-fifth of those were carried out in Trump's name.

"What happened is in the wake of the election we just saw [hate crimes] across the United States against Jews, but also against immigrants and also against Muslims, that were the major populations that he attacked during his campaign."

Beirich added that xenophobic rhetoric targeting immigrants and particularly Muslims, shares "disturbing parallels" with the rise of European anti-Semitism, which often coincided with nationalism, during the 1930s and 1940s. She also noted that Britain, too, saw a skyrocketing of anti-Muslim crimes following Brexit, the country's referendum on leaving the European Union.

"So, when Hitler rose to power it started with a wave of violence like this," Beirich added.

She also explained that in today's political climate, it's critical to commemorate the Holocaust.

"If everything goes completely to hell, you've got genocide, you demonise populations enough, that's where you are heading," Beirich said.

"You don't want to start going down that road. And the Holocaust is just this horrific reminder of what can happen. That's when mass slaughter can occur. We shouldn't even be talking about this, that's why it is so tragic, you know, that we have to be keep reminding ourselves of the Holocaust. It's embarrassing."

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'Make sure that doesn't happen again'

For Riteman, the Polish Auschwtiz survivor, such reminders plague him daily.

The black tattoo ink on Riteman's left arm - the numbers, 98706, his Auschwitz prisoner ID - are for ever etched there. Although the ink on his arm has faded, the horrific memories have not. The pain - and bitterness - from his time in Auschwitz still rings heavily in his voice.

"That's got to be told to our children, our grandchildren, great, great, great grandchildren. So long as the world exists, they should make sure that doesn't happen to anybody. Period."

Today, Riteman is 95. He's tired, and hard of hearing. Yet, he's still quite spry. At his quaint Canadian home in Halifax, Nova Scotia, which he shares with his 85-year-old wife Dorothy, whom he met in Montreal in 1947, Riteman stares off into the distance.

For decades, he didn't speak about the horrors of the Holocaust but it's a subject he now discusses openly - and something he treats as a duty - largely, so history doesn't repeat itself.

"You people are lucky," he said. "You're living in heaven. You don't even know it. I want you to wake up and make sure it doesn't happen again. That's the reason I'm speaking in schools, universities. Make sure [you] don't hate nobody, don't do no harm to anyone. Be a good person. Maybe we could make a better world to live for everybody."