Roger Agnelli, a former banking executive who helped turn the Brazilian company into a global mining giant, died on Saturday when his private plane crashed in São Paulo, Brazil. He was 56.

Mr. Agnelli, his wife Andrea and their children, Ana Carolina and João, were en route to a wedding in Rio de Janeiro when the turboprop monoplane slammed into two homes just minutes after taking off, killing all seven people aboard, according to Reuters and a statement released by .

The others on the plane were the pilot and the spouses of the Agnellis’ children. The company statement did not indicate the cause of the crash.

Mr. Agnelli took over as president and chief executive of Vale in 2001 after nearly 19 years at one of the country’s largest banks, , which is a major shareholder in Vale. The company was at the end of a process of privatization that had begun in 1997, though the government retained a stake in the company.

Under Mr. Agnelli, Vale grew into one of Latin America’s biggest companies: the second-largest mining company in the world at the time, and the largest producer of iron ore.

Known by some as the “Iron Man,” Mr. Agnelli was a tough negotiator and a bold executive who expanded the company’s reach into markets in Asia, particularly China.

In 2006, he presided over the company’s $18 billion purchase of Inco, a Canadian nickel producer, the largest acquisition that had ever been made by a Latin American company, Vale said.

Seven years into his tenure, the company’s market value had increased from $8 billion to $150 billion, according to the book “Global Latinas: Latin America’s Emerging Multinationals” by .

In 2013, Mr. Agnelli was named to the No. 4 spot on Harvard Business Review’s list of the best performing chief executives in the world, behind Steve Jobs of Apple, Jeff Bezos of Amazon and Yun Jong-yong of Samsung.

According to Ms. Casanova, Mr. Agnelli “challenged the traditional notion that mines are best run in enclaves separate from the local community,” citing the construction of a model mine in 2004 in the Brazilian state of Paraná.

“We brought in water and sewage treatment, a school, a police station and technical training,” Mr. Agnelli said in an interview quoted in the book. “As modern miners we can’t just be technicians. We need to listen to the community and be less arrogant.”

Mr. Agnelli was ousted in 2011 after friction with the Brazilian government, which pushed for the company to invest more in the country’s workers and industries.

The company had seen its value double in the previous five years, but Mr. Agnelli angered government officials by laying off more than 1,000 workers and slashing investments in Brazil.

Mr. Agnelli was born on May 3, 1959, in São Paulo.

In recent years, he had worked on his own mining venture, AGN Participações.

Information on survivors was not immediately available.