By Angus Roxburgh
BBC News, Riga
In a park in the Latvian capital Riga, a small group of protesters gathers, all Russian, some wearing paper hats inscribed with the word "Alien".
Ignored by the authorities, 'non-citizens' are appealing to the EU
Latvian police carry out a small, bureaucratic piece of harassment. With a tape, and much officiousness, they measure the distance between the demonstrators and the nearest public building, a school on the other side of the road.
The protest is two metres too close, so the police move it a little further down the path.
The protesters don't mind. They are there to object to a much greater injustice.
More than 450,000 Russians and native Russian-speakers - out of a total Latvian population of 2.3m - are classed as "non-citizens" because they have failed (or refused) to take a test in Latvian language and history, which would allow them to have citizenship.
This was local election day, and they were protesting about the fact that as "aliens", despite having lived in Latvia all their lives, they had no right to take part in the elections - whereas citizens of other EU countries could vote if they had lived there for a mere six months.
"I was born here," said one young man. "I pay the same taxes as Latvians. Yet I'm not allowed to vote for the politicians who spend those taxes."
"I'm here to protest against the government's policy of dividing society along ethnic lines," said another.
The fate of the non-citizens - who account for 20% of the entire population of Latvia - is a complex one.
When Latvia gained independence from the Soviet Union in 1991, it granted automatic citizenship to those who had lived in the first independent Latvian state - between 1918 and 1940 - but not to those who immigrated here after the war, when Latvia was occupied by the Soviet Union.
Latvia suffered hugely under Soviet rule.
Thousands were arrested and sent to Siberian labour camps, or executed, during the Stalin years.
Later, hundreds of thousands of Russians, Belarussians and Ukrainians flooded into the republic under a deliberate policy of Russification. The Latvian language was squeezed out of official use.
MEP Tatjana Zdanoka uses her position to highlight the issue
Latvians were resentful citizens of the USSR. By 1991, they comprised only half of the population of their own country, while in Riga only a third were Latvian.
Even today, Russian is heard as commonly as Latvian on the streets of Riga.
But the government is determined to revive the Latvian identity. It says its policy towards Russians who immigrated here during the Soviet period is aimed not at punishing them for the sins of the Soviet regime (as some suspect) but at ensuring that they learn Latvian and integrate fully into society.
In order to naturalise, Russians must take a test in Latvian, and pass an exam about Latvian history - in which they must "correctly" answer that the country was occupied and colonised, not liberated, by the Soviet Union in 1945.
Many of the Russians at the demonstration on election day said they found that psychologically difficult. They said they wanted to integrate (and many could speak Latvian), but they found the idea of applying for citizenship humiliating.
"I lived here - same as them - and I was a citizen of the USSR," said a middle-aged woman. "They deprived me of my citizenship, and now I must apply to become one! I just won't do it."
Separate, but together
Tatjana Zdanoka is Latvia's only Russian member of the European Parliament and uses her position to publicise the position of the Russian minority.
She says her mother, who has lived in Latvia for 60 years and worked here for 45 years as a schoolteacher, has no right to vote.
"She is 83 and has bad eyes. Of course she's not capable of taking any kind of exam."
Facts about Latvia
Latvia was independent from 1918 to 1939
After World War II it was a part of the USSR
It regained independence in 1991
700,000 Soviet-time migrants and their children became non-citizens
By the time Latvia joined the EU in 2004, this figure had dropped to around 450,000
Latvia's total population is 2,3m (including non-citizens)
Igor Vatolin, a journalist on the newspaper Chas and a Russian rights activist, said the Latvian Popular Front, which led the fight for independence at the end of the 1980s, promised citizenship to everyone living in the republic.
"But they reneged on that - even though thousands of Russians voted with them in favour of independence in the referendum of 1991," he said.
There is no ethnic strife in the streets of Latvia. The two peoples live peacefully together. But politicians on both sides, and in Russia itself, stir things up.
Moscow rarely misses a chance to complain at international meetings of Latvia's "human rights abuses", while the head of the Latvian parliament's foreign affairs committee, Aleksandrs Kirsteins, has described the non-citizens as "civilian occupiers".
He called for an agreement with the Russian government under which all the unwanted foreigners would be herded on to trains and shipped back to their "ethnic homeland" - with a brass band playing on the platform to see them off.
Latvia's two communities deserve credit for by and large ignoring such provocative statements. Despite the bitterness and insecurity on both sides, they have succeeded in forging a peaceful co-existence - somewhat separate, but together.