Maj Gen James Johnston was faced with 40,000 prisoners at the Bergen-Belsen camp and set up a hospital to treat them for typhus, TB and starvation.
His son, Anthony Johnston, said: "He had to deal with people dying by the hundreds every day."
The plaque was unveiled in Northiam, East Sussex where Gen Johnston lived.
Born in Glasgow, he moved to the village with his family in 1973.
About 60 people, including members of Gen Johnston's family, gathered for the unveiling at the pump house on the village green.
Gen Johnston was commanding a mobile medical unit close to the German-Dutch border in April 1945.
He was ordered to move his unit to take charge of the sick and starving at Bergen-Belsen, which had just been liberated by the British.
Around 70,000 people had died at the camp in northern Germany.
Mr Johnston said his father had been reluctant to talk about his World War Two experiences, due to modesty and wanting to block out such a traumatic event.
"There were times in his life when former inmates, who he had come across at the time, got in touch with him and wanted to acknowledge him," Mr Johnston said.
"Other than that, he didn't talk about it."
In an account which is now in the Holocaust Museum in Washington, Gen Johnston wrote: "Little did I know that I was about to be faced with the greatest test of my career, with a situation that would remain engraved on my memory for the rest of my days.
"[It] would instil in me a lasting abhorrence not only of those who had perpetrated this crime on humanity, but also of those who had condoned it."

The 35-year-old, who played six Super League games for Hull KR in 2011 before moving to French rugby union side Toulon, was at Manly last season.
He played 290 NRL games during his 15-year career spent with five clubs, including Canterbury, where he won the 2004 Premiership.
"Willie knows the job a prop has to do," coach Laurent Frayssinous said.
"He is a physical and aggressive player, both in attack and in defence and we have spoken a lot about the quality of our group and he is really excited to join the club."
Frayssinous' Dragons side have lost their first two games in Super League this season, with defeats by Wigan and Hull FC.
Veteran front-rower Mason scored seven tries and played 24 tests for the Kangaroos, including the famous Great Britain 2006 Tri-Series defeat in Sydney where he struck Stuart Fielden and was involved in a scuffle with tourists captain Jamie Peacock.
He also played 13 games for the Blues in State of Origin, scoring once.

Veteran striker Peter Weatherson bagged a first-half brace, including a penalty, to put the visitors firmly in control at Links Park.
Matthew Flynn and Josh Todd both struck from close range around the hour-mark.
Todd added his second of late on, with Jim Chapman's side rising to fourth, one point clear of Queen's Park, while Montrose drop to ninth after Berwick Rangers and Arbroath both won.

Stevens made his home debut in their 19-13 loss to Ealing, having joined the club after leaving financially-stricken London Welsh last month.
"We're pushing for top four, we want top four," the ex-Nottingham, Worcester and Plymouth Albion centre said.
"We want to do really well in the British and Irish Cup and we want to do as well as we can."
He told BBC Radio Jersey: "This club needs to be pushed forward and I think they definitely are on the right road for doing that."
The island side are currently eighth in the Championship, but are just seven points behind fourth-placed Ealing and point further back from Doncaster in third.
For the latest rugby union news follow @bbcrugbyunion on Twitter.
A plaque has been unveiled in memory of an Army medical officer who treated prisoners at a German concentration camp in 1945 following its liberation.
[NEXT_CONCEPT]
Catalans Dragons have signed former Australia and New South Wales prop Willie Mason on a one-year deal.
[NEXT_CONCEPT]
Annan Athletic moved into the League Two play-off places, routing Montrose.
[NEXT_CONCEPT]
New Jersey signing Heath Stevens says the club are capable of reaching the Championship play-offs.