'It's just a book'

Martin Schulz, the chairman and chancellor candidate of Germany's Social Democratic Party (SPD), has kept a diary for more than 30 years. A volume for each year, and "exactly one page for each day," he admitted in his book, entitled "Was mir wichtig ist" [What matter to me].

His first reaction was: what a crazy request - write a book in an election year? Then it occurred to him that he needed to take time "to process the things I've experienced, things that have moved me and things I worry about."

The book is honest, touchingly personal at times, but also very political. Quite simply, Schulz explains Schulz the chancellor candidate with references to his life, experiences and conversations.

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A chancellor candidate up close

Many parts of the book center on Würselen, near the western German city of Aachen. This is Martin Schulz's hometown and near where Germany, Belgium and the Netherlands meet. It's where he grew up,  where he experienced both the high points of his life, and the lows of alcohol addiction, where he played football, joined the SPD's youth wing, the Young Socialists, and started two careers, his professional one as the owner of a bookshop and his political one as the local mayor.

"For me, above all, it's my family, my neighbors and friends who keep me down-to-earth. There's no 'Mr. Chairman' or 'the candidate' to them, I'm just Martin," he said.

Würselen is like a burning lens in the biography of Martin Schulz. His ideas and his political convictions have much to do with this small town in North Rhine-Westphalia, with what Schulz and his family experienced there.

Read more: Martin Schulz - from 'pig' to top politician

Europe: a peace project

Schulz devotes an entire chapter to his parents, who married in April of 1940, just before his father, Albert Schulz, was conscripted as a soldier in the Wehrmacht. He wanted to give his wife social security. If he didn't come back from the war, she could count on receiving a widow's pension.

Though his parents survived, Schulz wrote, "Their grim experiences in the war shaped their lives until their dying days." As a child, he learned to join his parents in swearing: "Never again!"

This also plays a role in Schulz's enthusiasm for the European Union as a project for peace, first as a member of the European Parliament and then as its president. For him, a man who grew up so close to the Netherlands and Belgium, the answer to the "collapse of civilization" of the two world wars was logical.

"The European Union was, is, and therefore will always remain, above all, a work of unification for peace," he said, adding that to him, Europe also means international responsibility - not in the sense of policing the world "but in well-understood self-interest, and in order to defend our values."

The SPD's chancellor candidate also makes clear what those values are: justice, education for all, equal pay for men and women, and combating ultra-nationalism.

A book, not a manifesto!

In an interview with the German public broadcaster RBB, Schulz insisted, "The book is not a book in which I make concrete political demands in the form of a party or election manifesto." That, in any case, won't be presented until June 25, at the party conference in Dortmund.

Can the publication of "What matter to me" provide Schulz with a boost in the polls? It's unlikely. After the initial hype surrounding his candidacy, his polling numbers for the Social Democratic Party have dropped. It now lies well behind Chancellor Angela Merkel's conservative Christian Democratic Union, on just 24 percent.

"Few countries are as free, as democratic, prosperous and socially secure as Germany," Schulz wrote. However, most Germans seem to ascribe this not to Martin Schulz's SPD, but to longstanding Chancellor Angela Merkel.