The Second World War tore Latvia to shreds: annexed by the Soviet Union, occupied by Germany, then occupied again by the Red Army, brutalised, degraded and devastated, Latvia suffered dictatorship, colonisation and mass murder.

For many in the small Baltic state, this was a civil war, with all the horror that word implies. One third of Latvia’s prewar population, perhaps 630,000 people, was lost between 1940 and 1954. Almost the entire Jewish population of 80,000 was wiped out. Both Soviet and German occupiers conscripted Latvians into their armies. Brother fought brother.

This is the grim battlefield into which the Labour and Conservative parties have both marched with a staggering lack of intellectual rigour and historical understanding. Both sides have cynically tried to deploy history for political gain, and both have got it wrong.

Last week David Miliband attacked the Tory alliance with Latvia’s right-wing For Fatherland and Freedom Party, one of its new friends in the European Conservatives and Reformists grouping in the European Parliament. Every year, the Foreign Secretary pointed out, this party celebrates those Latvians who, in 1944, fought for the Waffen-SS in a doomed attempt to hold back the Soviet troops. For Mr Miliband, this is evidence of Tory association with some of Europe’s most unsavoury neo-Nazi elements.

The Conservative Party chairman, Eric Pickles, however, argues that the two Waffen-SS units making up the Latvian legion consisted of conscripts, and that Mr Miliband is recycling Soviet propaganda by condemning them. By this interpretation, the Latvian SS legion was made up of patriotic anti-communists battling Soviet occupation, and therefore worthy of celebration.

History seldom conforms to the easy platitudes of politics. Latvia’s wartime experience was messy, brutal and morally complex. But the story of the Latvian SS legion is suddenly casting a shadow over British politics: this slice of the distant past is now part of David Cameron’s future.

Some 65,000 Latvians, mostly teenagers, were enrolled in the legion, starting in 1943. The majority were conscripts, forcibly mobilised to prop up Germany’s collapsing eastern front. Offered a choice between a Waffen-SS uniform or transfer to a German slave-labour camp, many saw no choice at all.

After the war, the American commissioner for displaced persons concluded: “The Waffen-SS units of the Baltic states are to be seen as units that stood apart and were different from the German SS in terms of goals, ideologies, operations and constitution.”

Even so, the ranks of the legion contained a substantial minority of racist killers, men who not only volunteered to sign the oath to Hitler, but did so eagerly. The mass murder of Latvian Jews in 1942 was ordered and directed by the Nazis, but Latvian extermination gangs enthusiastically participated in the genocide. Stories of Latvians helping Jews to escape the Holocaust are shamefully rare.

Many of these experienced Latvian thugs transferred to the SS legion in 1944. Supporters of the legion insist that its members were not supporting Nazism but defending Latvia: the truth is that many were fighting not only for Hitler against the Allies, but doing so with ideological fervour.

In Britain, we still tend to see the war in shades of black and white, a simple morality tale of good versus evil. For those under occupation — in France, Latvia or the Channel Islands — the conflict was played out in grimy shades of moral grey. Some collaborated keenly, others did so unwillingly, a few resisted valiantly and most merely tried to stay alive.

When Stalin annexed the Baltic states in 1940, his secret police tore through Latvian society in an orgy of arrest, torture and murder. Initially, and unsurprisingly, when the Nazis marched into Riga in 1941 some Latvians hailed them as liberators. In 1944, the wheel turned again, the Soviet grip was reasserted, and remained in place for the next 47 years. Many who joined the Waffen-SS genuinely thought they were fighting the devil they already knew from just three years earlier.

This does not make Latvia’s SS legionnaires into admirable warriors, or even victims, as their more extreme supporters claim, but it does put their role into perspective.

A sense of perspective, however, has been entirely lacking since this small, sad chapter of Latvian history was dragged into British politics. For Mr Miliband, the Latvian legion is a Nazi crime, and any party that supports the annual parade in its memory is neo-Nazi, a useful cudgel with which to beat the Tories.

An even greater responsibility to see history clearly lies with the Conservatives, who have sought to play down the role and responsibility of the legion. Many of the legionnaires may have joined up under mitigating circumstances, but some were appalling criminals, knowing collaborators in genocide.

They were not “tragic heroes”, as maintained by Roberts Zile, leader of the For Fatherland and Freedom Party. For the most part they were ordinary, ignorant, scared young men who ended up on the wrong side. They should not be lionised but remembered as salutary evidence of the horrible moral confusion wrought by war.

The Board of Deputies of British Jews is right to question David Cameron over the Tory partnership with right-wing groups in Eastern Europe: the problem is not guilt by association but Conservative attempts to simplify the past and frame Latvia’s SS soldiers simply as unwilling, and by implication innocent, conscripts.

Latvian legionnaires were not all evil Nazis, and nor were they brave freedom fighters; most were something in between. Politicians may try to dragoon history into service, but the facts usually refuse to march in straight lines.

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