Germany and Turkey held a ceremony Wednesday to mark the 50th anniversary of a labor agreement that brought millions of Turkish workers to Germany, with the two countries\' leaders calling for more integration of those \"guest workers\". Accompanied by Turkish Prime Minister Recep Tayyip Erdogan, German Chancellor Angela Merkel spoke highly of the labor pact, signed in 1961 between then-west Germany and Turkey for introducing more Turkish workers to Germany to power the country\'s post-war industrial expansion. \"Leaving relatives and friends behind to work in a foreign country, using a foreign language in a foreign culture means a brave step for people,\" Merkel said in the ceremony, attended by many first so-called \"guest workers\" setting foot on German soil decades ago. At first, the agreement set a two-year limit for working in Germany, but later relaxed restrictions. As a result, instead of returning to their motherland, many Turkish immigrants chose to settle down here with their families. Until now, some 3 million Turks or Germans of Turkish origin are living in Germany, making the country\'s largest ethnic minority. Experts said the labor pact in the cold-war era exerted an unexpected long-term influence in history, not only changing lives of millions of people, but also transforming the German society and its relationship with Turkey. Germany was \"no longer a foreign home\" for the Turkish immigrants and their children, Erdogan said. \"I\'d like to say it in German -- Wir sind zusammen (We are together).\" However, making two peoples together seems not easy. The integration of those immigrants was always a rich and sensitive topic in Germany, as some German are complaining that some Turkish immigrants lived in an isolated world of themselves -- speaking little German, adhering to their own way of life, quitting school at a young age, having no job and relying on social welfare.