He was promoted to vice chairman of the conglomerate in 1989, starting his full-fledged preparations to be the future top manager.

Besides his position at the company, Koo was named as the vice chairman of the Federation of Korean Industries, one of the major business lobbying groups in the country in 1989, which helped him expand his networks in the South Korean industry.

After working for the conglomerate for 20 years, Koo was named as the new head in 1995, inheriting the leadership from his father, who had opted to retire. He officially took the reins of the conglomerate five years later.

Koo moved aggressively to generate new opportunities, in such areas as telecommunications, auto parts, displays, energy and biotech, while also expanding the group's already strong presence in electronics and chemicals.

The Lucky-Gold Star Group also became LG Group right after Koo took the helm, which contributed to enhancing the group's brand reputation, particularly abroad.

Despite splitting off a handful of affiliates, such as GS, LG, LIG and LF, the conglomerate still posted sharp growth, raking in 160 trillion won ($148 billion) in sales last year, compared to around 30 trillion won posted in 1994. The group's overseas sales also shot up 10-fold over the cited period to reach 110 trillion won.

Some of his major achievements include fostering LG Display Co., helping make it into one of the leading players in the global organic light-emitting diode display market. LG Chem Ltd. also became a major global company under Koo's leadership. The company's operations include its rechargeable battery business that has considerable growth potential going forward.

He also successfully launched LG Uplus Corp., which is now one of the country's three mobile carriers.

One of Koo's more recent achievements was establishing LG Science Park in western Seoul this year by injecting around 4 trillion won, paving the way for the group to study deeper into future growth engines.

He was also a well-known baseball fan, which contributed to the buildup of the LG Twins Baseball Club.

His acquaintances said he enjoyed fishing and golf and also liked to watch birds at the Han River. Others remembered him as a well-mannered and friendly person who was never late for appointments.

While Koo only had two daughters, he adopted a son -- Koo Kwang-mo -- from his younger brother Koo Bon-neung in 2004. The adopted son is expected to become the next leader of the conglomerate. (Yonhap)