Marcus Rashford, Jadon Sancho and Bukayo Saka were all subjected to abusive posts in the wake of their missed penalties in the shoot-out.
Figures within the sport, from the Government and even the Duke of Cambridge were united in their condemnation for the abuse, and Three Lions captain Kane said on Twitter: “Three lads who were brilliant all summer had the courage to step up and take a pen when the stakes were high.
“They deserve support and backing not the vile racist abuse they’ve had since last night. If you abuse anyone on social media you’re not an England fan and we don’t want you.”
England boss Southgate said at a press conference on Monday morning: “For some of them to be abused is unforgivable really.
“I know a lot of that has come from abroad, that people who track those things have been able to explain that, but not all of it.
“It’s just not what we stand for. We have been a beacon of light in bringing people together in people being able to relate to the national team, and the national team stands for everybody and so that togetherness has to continue.
“We have shown the power our country has when it does come together and has that energy and positivity together.
“We heal together as a team now, and we’re there for them, and I know that 99 per cent of the public will be as well.”
Midfielder Jude Bellingham labelled the abuse “hurtful but not surprising” and insisted he would “never get bored of saying that more needs to be done”.
Defender Reece James posted: “We learn more about the society when we lose, far more than we learn when we win.”
Kalvin Phillips, who started every match for England, added: “Absolutely disgusted at the unnecessary racist abuse I’ve seen online directed at my team-mates. Nothing but love and respect for my brothers for their courage.”
Arsenal released a statement stating their pride in how Saka had represented his club and his country during the tournament, which had turned to sorrow when witnessing the abuse the 19-year-old suffered.
“We are sad to have to say we condemn the racism of a number of black players,” the statement read.
“Our message to Bukayo is: hold your head high, we are so very proud of you and we cannot wait to welcome you back home to Arsenal soon.”
Manchester United compiled messages of support for striker Rashford on their website, and a statement introducing the posts said: “It takes tremendous guts to take a penalty under such pressure, when the entire nation is anxiously watching on, so we are proud that Marcus was brave enough to step up.”
The Duke of Cambridge, who is president of the Football Association, said he was “sickened” by the abuse.
“It is totally unacceptable that players have to endure this abhorrent behaviour,” he wrote on Twitter.
“It must stop now and all those involved should be held accountable.”
Prime Minister Boris Johnson, Home Secretary Priti Patel and Culture Secretary Oliver Dowden all condemned the abuse, with Johnson telling a press conference: “To those who have been directing racist abuse at some of the players, I say shame on you and I hope you will crawl back under the rock from which you emerged.”
But England defender Tyrone Mings hit out at Patel, who on Monday morning said she was “disgusted” at the abuse and that it had “no place in our country”, having said at the start of the tournament that fans had a right to boo players for taking the knee in protest against racism.
In response to Patel’s tweet, the Aston Villa man posted: “You don’t get to stoke the fire at the beginning of the tournament by labelling our anti-racism message as ‘Gesture Politics’ and then pretend to be disgusted when the very thing we’re campaigning against, happens.”
Gary Neville also criticised Johnson’s leadership, telling Sky News: “Gareth Southgate and the players a few weeks ago, about five days on the trot, told us they were taking the knee to promote equality and it was against racism.
“The Prime Minister said it was OK for the population of this country to boo those players who were trying to promote equality and defend against racism. It starts at the very top.
“I wasn’t surprised in the slightest that I woke up to those headlines; I expected it the minute that the three players missed.”
Neville’s former England and Manchester United team-mate Rio Ferdinand highlighted that the players who missed would have been idolised by those who abused them had the result gone the other way.
He tweeted: “These same idiots only days ago would have been celebrating the brilliance of a (Raheem) Sterling or a Saka or a (Kyle) Walker for their efforts in an England shirt. You can bet ya last pound also that they would have sung the Raheem Sterling song almost bursting the veins in their bodies doing so.
“But England lose and that joy and sense of being united immediately evaporates and our black players become the target.”
Anti-discrimination body Kick It Out and players’ union the Professional Footballers’ Association again called on social media companies and the Government to stamp out the abuse on online platforms.
Kick It Out chief executive Tony Burnett said: “The social media companies need to do more to stamp out abuse on their platforms, and the Government also need to step up and keep its promise to regulate. The Online Safety Bill could be a game changer and we aim to help make that happen.”
The PFA said in a statement: “Social platforms must permanently ban all offending accounts and proactively compile evidence to give to the police to pursue prosecution.
“There has been talk of strong commitments and tough measures from the social networks. Based on the evidence so far, we’re not buying it. Social networks, we need you to do better.”
Former England rugby international Ugo Monye, who attended the final, told BBC Radio 5 Live: “The Government don’t do enough, they don’t say enough.
“It’s hard to fix a problem until you acknowledge the problem and at the moment you’ve got a lot of people unfortunately in senior positions, and members of the public, who deny that (racism) is a thing.”
Twitter said it had proactively removed more than 1,000 posts over the past 24 hours which violated its policy and also taken swift action to permanently suspend a number of accounts.
Facebook, which owns Instagram, said it tries to remove harmful content as quickly as possible and encouraged people to use the tools it offers to block abuse.
The Metropolitan Police is investigating the abuse, while Wolves said one of their supporters had been reported to West Midlands Police after posting a racist tweet and Leyton Orient have already issued a lifetime ban to a fan.
Meanwhile, the UK Football Policing Unit (UKFPU) has also launched an investigation into the racist hate targeted at players following the match.
Chief Constable Mark Roberts, National Police Chiefs’ Council Football Policing Lead, said: “Investigations are under way to identify the offenders.
“We have had excellent support during the tournament from Facebook, Instagram and Twitter and enquiries are already being progressed.
“When an offender’s details are identified, this is passed onto the relevant local force to investigate further and take appropriate action in conjunction with the CPS. The UKFPU is also working closely with the FA, ensuring the relevant support is in place where needed.”