Tycoon Goh Cheng Liang has made a mint in businesses ranging from health care to instant noodles, but his decision to return to his first big score - paint - has made him Singapore's wealthiest person.

The Bloomberg Billionaires Index last week put him in that enviable spot, calculating his net worth at $11 billion.

This is just one more milestone for the 86-year-old, whose life story has been filled with the kinds of twists and turns that would tax a Hollywood scriptwriter.

The reclusive magnate, who has only given one interview in the past two decades, grew up in poverty, spending the first 12 years of his life squeezed into a rented room with his parents, three sisters and a brother.

He completed only primary education in a Chinese school as his family was too poor to pay for further studies.

When World War II hit Singapore, his parents sent him to Muar, Johor, where he helped his brother-in-law sell fishing nets. Back home, his father was unemployed throughout the Japanese Occupation while his mother washed clothes and his sister sold soon kway.

When Mr Goh returned to Singapore in 1943, he made his first attempt at business by selling aerated water but the venture failed.

"No experience, went bust, everything finished, all my Tiger notes (Straits Settlement currency) disappeared," he said in an interview in 1997.

Mr Goh then took up an apprenticeship at Tan Chong Huat Hardware at South Bridge Road in 1945 and was soon promoted to salesman.

In 1949, the British army auctioned off war supplies. Sensing a deal, Mr Goh bought barrels of cheap "rotten paint" from them.

He had acquired a little knowledge about paints from a short training course in Denmark while he was at the hardware store.

Armed with that knowledge and a Chinese dictionary on chemicals, he got to work on the paints, mixing colours and adding solvents. The result was his own line of Pigeon Brand paints.

It was the outbreak of another conflict - the Korean War of 1950 - that really propelled Mr Goh's business, as import restrictions boosted demand for his locally made paints.

By 1955, he had opened a retail outlet and went back to Denmark, this time to learn paint manufacturing technology. His reputation grew and in 1959, Sim Lim Investments, then an agent for Japan's Nippon Paints, approached him to become a distributor. Two years later, he formed a joint venture called Pan-Malayan Paint Industry with Nippon, Sim Lim and the Charoen Pokhphand group of Thailand.

However, the partnership did not last long: Sim Lim lost interest in the paint business while the Thai group wanted to focus on animal feeds.

Mr Goh stuck to paints, setting up a Nippon mixing plant in Singapore in 1963 and another in Thailand in 1967.

A few years later, his business once again became an unintentional benefactor of geopolitical trouble. This time, it was the oil crisis of 1973, which jacked up the price of paint, which has crude oil as a key ingredient.

"My fortune was built from these two events - the Korean War and the oil embargo," Mr Goh has said.

The fat margins he earned from paints were channelled into what became his new passion - property.

He turned out to have a natural flair for the game, developing Mount Elizabeth Hospital and residential and commercial projects in Singapore, Hong Kong, China and the United States.

Perhaps his most famous landmark is Liang Court at Clarke Quay, which he started in 1985 on the site where he was born and lived with his family until he was 12.

Launched just before the start of a recession, critics said the shopping and office complex would not be able to draw crowds away from Orchard Road.

But they had underestimated Mr Goh's business savvy and the extensive network of Japanese contacts he had built up by then.

He knew Liang Court had to have strong anchor tenants and this he offered with the opening of Daimaru department store and Hotel New Otani, both from Japan.

His network also helped fill up the units at serviced apartment Liang Court Regency, now known as the Somerset Liang Court, which remains popular among Japanese expatriates. His son Goh Hup Jin once commented that his father had "an almost uncanny knack when it comes to properties".

It was not long before the empire grew to encompass all kinds of businesses, including hotels, manufacturing, food, finance and pharmaceuticals.

In 1974, Mr Goh divided his group into two - he set up Nipsea Holdings International to take care of all the Nippon Paint joint ventures and established Wuthelam Holdings to oversee everything else.

Over the following decades, the businesses grew from strength to strength, mostly out of the public eye.

By the 1990s, Mr Goh had begun delegating responsibility and taking more time to enjoy the fruits of his labour.

In 1991, his son Hup Jin took over the reins at Wuthelam Holdings after having poached Hewlett Packard Singapore boss Koh Boon Hwee to join the business.

In the meantime, Mr Goh set up Yenom Holdings, a private company to "house" 30-plus old staffers who were displaced by an organisational revamp launched by Mr Koh.

Yenom was meant to be a home for all the things that did not fit under the restructured Wuthelam but within six years, it had become a force of its own, with investments ranging from real estate in New Zealand and Fiji to Tung Lok Shark's Fin restaurants.

In fact, Yenom became the largest private part of Mr Goh's empire with 363 companies under its control by 1997 and more than $2 billion in turnover.

By that time, Mr Goh said he was "75 per cent retired", spending half of each month on board White Rabbit II, his US$30 million luxury yacht with a three-deck atrium, solid mahogany and marbled interior. And this is just one of his collection of boats.

Opulent as that may sound, the yachts and catamarans are rare indulgences for the tycoon, whose favourite food is Teochew porridge from the hawker centre and whose office in Genting Lane is said to be sparsely furnished and decorated with plastic flowers.

Through his Goh Foundation, he has also been a champion of philanthropic causes, donating tens of millions of dollars to charity and research.

Just last year, the foundation gave $50 million to the National Cancer Centre to fund research and a proton-beam treatment facility. In 2009 it also donated $12 million to the Yong Loo Lin School of Medicine to help improve the treatment of childhood cancer.

As he began to enjoy life and give back to society, Mr Goh also started unwinding his corporate stakes. He sold his 59 per cent holding in Liang Court to Pidemco Land in 1999 while Omni Industries was sold to Celestica of Canada in 2001 and Superior Multi-Packaging was taken private.

But clearly, that was not the end of the businessman's savvy wheeling and dealing.

These days, he has his focus back on the business that first made his wealth - paint.

Last year, Wuthelam Group inked a deal with Japan's Nippon Paint that more than doubled its share of Nippon Paint South-East Asia Group, or Nipsea, to 39 per cent.

Nipsea, which operates in 15 Asian countries, is Asia's biggest paintmaker and likely the fourth-largest globally, according to Mr Akihiro Kishi, a Tokyo-based analyst at IHS Chemicals, which researches the paint industry, a Bloomberg report said last week.

The move helped to boost Mr Goh's fortune to $11 billion, according to Bloomberg, making him Singapore's wealthiest person, a spot previously held by the more well-known Mr Wee Cho Yaw, the largest shareholder of United Overseas Bank.