(FORTUNE Magazine) – Pick a viewpoint from any office high rise in St. John, New Brunswick, and look around. You will see the largest oil refinery in Canada, the first deepwater oil terminal in the Western Hemisphere, a shipyard, a dry dock, a TV station, a radio station, a newspaper building, bus and truck companies, gas stations, convenience stores, and laundromats. Kenneth C. Irving owns them all. Chances are he owns the high rise you are standing in as well. Among Canada's billionaires, Irving, 88, is the richest and least known -- even though he dominates the economy of New Brunswick and makes no apologies for it. Tall, bald, litigious, and secretive, K.C., as he is known, has built an empire worth up to $6 billion. That at least is the estimate of journalist Diane Francis, author of Controlling Interest, a well-researched book about wealthy Canadians published last year. Other published estimates put the figure at $5 billion. Canada's lenient antitrust laws enable people like Irving to accumulate enormous wealth and power; its equally lenient disclosure requirements enable Irving to keep his affairs known only to himself, God, and the Canadian government, with which he has had some epic battles. In the 1970s, after the government discovered that Irving owned all five English-language newspapers in New Brunswick, it sued him for violating Canada's antitrust act. A lower court ordered him to sell two of the papers and pay a $150,000 fine. But the Supreme Court reversed the decision, ruling that the act was worded too vaguely to snare Irving. The concentration of Canadian wealth appears to be increasing. Nine families control nearly half the shares of the 300 companies that make up the composite index on the Toronto stock exchange. The billionaires among them include the Bronfmans (see page 153); the three Reichmann brothers, Albert, Paul, and Ralph, whose Toronto-based Olympia & York Developments Ltd. has become the biggest real estate developer in North America; the Weston brothers, Galen and Garfield, the third generation in a company that began delivering bread in 1882 and is now one of the world's biggest food businesses; and the Thomsons, who own Hudson's Bay Co. and more newspapers in North America than anyone else. K.C. Irving fails to show up as a major figure on the Toronto Stock Exchange, but that is only because his fortune is so private. The son of a Scottish immigrant in New Brunswick, Irving served as a pilot in World War I and went into business in 1924 selling Fords in his hometown, Buctouche. The car business led to selling gasoline, and then it seemed to make sense to build a refinery and to acquire the trucks and ships to move the oil and gasoline. That led to a shipyard to build the tankers. Irving's holding company, K.C. Irving Ltd., now manages about 300 privately owned firms, mostly in New Brunswick and Quebec. Irving also operates a dozen companies in the tax haven of Bermuda, where he lives the requisite six months. Much of the empire's day-to-day business is done by Irving's three sons, James, John, and Arthur. The sons, whose childhood nicknames were Gassy, Oily, and Greasy, are grown men in their late 50s now. Although said to be less wily than the old man, they are known as hardworking, tough, and competitive. The family's uncompromising attitude toward competition is revealed in the bulletins periodically distributed to the stores in St. John. A recent one said: ''All Irving convenience stores are to handle Irving garbage bags and Irving handy kitchen catchers . . . EXCLUSIVELY!!!'' Since 1979 the Irvings have been fighting a charge by Revenue Canada that they attributed $107 million in profits to an oil subsidiary in Bermuda that should have been taxed in Canada. The defense and prosecution have finally rested their cases, and the court is expected to issue a decision later this year. Whenever the Canadian government inquires into the Irvings' affairs, the family's response is that their business is no one else's. Arthur once told a federal court that his father ''believed he should control as much of his destiny as he could.'' The Thomsons of Toronto are almost as rich as the Irvings, and considerably more public. The family recently acquired five newspapers in Minnesota, North Carolina, and West Virginia, raising their total in the U.S. to 107, all small and undistinguished. In Canada they own 52 papers, including the country's most prestigious daily, Toronto's Globe and Mail. Kenneth R. Thomson, 64, a shy, scholarly man who is entitled to call himself Lord Thomson of Fleet, but who usually goes as plain Mr. Thomson, presides over the publishing empire, the family's oil interests, and the retail chains of Hudson's Bay Co. Kenneth's rough-and-tumble father, Roy (who was awarded the hereditary title in 1964), got his start buying a small radio station in northern Ontario in 1931. Not until he was in his late 50s did he become a millionaire and launch himself as a newspaper magnate. He moved to England, purchased the Scotsman of Edinburgh, and then a chain of newspapers that included the Times of London and the Sunday Times. While he was in Britain, his friend J. Paul Getty dragged him reluctantly into making an investment in North Sea oil that paid off big. After Roy's death in 1976, Kenneth moved company headquarters back to Toronto. And a year-long strike at the Times persuaded him to sell that paper to Rupert Murdoch. Today Kenneth, his sister, Phyllis, and their seven children control a $5.5-billion fortune centered on three major companies: --International Thomson Organisation Ltd., which owns regional newspapers in England; specialized publications such as Jane's annual books on ships and aircraft; numerous business and professional publications in North America, including Ward's Auto World; travel companies; and oil interests in the North Sea and North America. The Thomson family controls 73% of the company's common shares, worth $2.55 billion. --Thomson Newspapers Ltd., which has 159 daily, weekly, and biweekly newspapers in Canada and the U.S. The 71% of the company owned by the family is worth $2.55 billion. --Hudson's Bay Co., which was chartered by King Charles II in 1670 to trade fur, and is now a $4.2-billion-a-year retail business that also has oil and real estate interests. After losing money steadily since the Thomsons acquired it in 1980, the Bay turned a profit last year. The Thomsons' 74% share of the company is worth about $400 million. Roy Thomson wanted the family business to be managed by Kenneth's male descendants. So earlier this year Kenneth launched his older son, David, 29, on the road to succession by making him president of Zellers Inc., a 31-store discount chain owned by the Bay. Like his father, David should find Canada a nice place to be a billionaire.