Germany's former "Chancellor of Unity," Helmut Kohl, appeared briefly in front of his home on his 80th birthday Saturday, as thousands of Germans added their wishes to the messages of congratulations from statesmen around the world, according to dpa. Kohl, who was chancellor from 1982-1998, is remembered for his role in events leading to the fall of the Berlin Wall in 1989 and German reunification the year after. The ailing statesman appeared briefly in front of his home in Ludwigshafen, some 600 kilometers to the south-west of Berlin, sitting in a wheelchair and accompanied by his wife. He waved at journalists, but said nothing. Kohl, who is still suffering from the repercussions of a serious head injury two years ago, had planned to spend his birthday with private guests at home. Official celebrations are due to take place in Ludwigshafen next month. German Chancellor Angela Merkel, who grew up in East Germany, thanked her former mentor for his "passionate personal commitment" and "firm belief in a united, free future for Germany and Europe," adding that it had a huge impact on the course of her own life. Former Soviet leader Mikhail Gorbachev, who enacted many of the reforms that led to the end of communism in eastern Europe, said the two leaders shared a determination to end the Cold War. "My father was badly injured in World War II, and Kohl's older brother never returned from the front. This helped us better understand one another in our quest for peace," Gorbachev told Russian daily Izvestija. George H W Bush, who was US president from 1989-93, described Kohl as "one of the most influential German statesmen of the 20th century," who would be judged positively for his role in the end of the Cold War and German reunification. "He was a wonderful and reliable ally and is still a good friend," Bush told German daily Mannheimer Morgen. Russian President Dmitry Medvedev congratulated Kohl in a telegramme, and said the statesman had also contributed to a new beginning in Russian-German relations. German President Horst Koehler said the success of German reunification was in a large part Kohl's doing. "All your life you were ready to perform your duty to our country. That has earned you an extraordinary degree of respect and trust from our fellow citizens," Koehler said. Thousands of Germans left messages of congratulation on a dedicated website, which also included comments from around the world. Well-wishers described Kohl as "the record chancellor," in reference to his 16 years in office, or the "father of German unity," - as well as "our old stubborn-head," or even "our chubby one," in reference to Kohl's large girth. One Turkish man praised Kohl for his "strong political ideas," and a congratulant in Poland wrote, "Thank you for your politics. Thank you for the reunification of Germany." "If I were German I would not have voted for you. But given all you have done for Germany without harming your neighbours, I realize I would have been wrong," wrote one well-wisher in the Venezuelan capital Caracas. Few messages referred to the donations scandal in the late 1990s, when it emerged that Kohl had accepted more than two million deutschmarks (1 million euros) in undeclared funds for his Christian Democrats (CDU). One person expressed pride that Kohl had never revealed the names of the donors. To this day, the former chancellor has refused to break his vow of confidentiality. As a result, Merkel has refused to reinstate his honorary chairmanship of the CDU. In a rare newspaper interview, Kohl spoke of his declining health, after he had an operation to remove his gall bladder in January. "I am doing well. To say I am doing really well would surely be an exaggeration, but I am turning 80 after all," Kohl told German daily Bild. Two years ago, Kohl suffered serious head injury after falling on the stairs in his home. He said the consequences were "dramatic." "For weeks I was barely responsive, and every movement was a huge effort, let alone trying to walk." The former chancellor said he still struggled to speak and walk, but had made huge improvements. Kohl, whose wife Hannelore committed suicide in 2001 after a debilitating allergy to light, remarried in 2005. "Without my wife I would no longer be alive, and if she were not with me, my life would be far less worth living," Kohl told the newspaper. Birthday celebrations in the reunified capital Berlin were cancelled due to Kohl's ill health. Instead, 1,000 guests will travel to his hometown of Ludwigshafen for an official reception on May 5. -- SPA