Publisher Alfred A Knopf announced on Tuesday that Gandhi's memoir, 'Belonging: A Journey of Love', will be released on November 10.
The book will explore her marriage into the Nehru-Gandhi family, the deaths of her mother-in-law Indira Gandhi and husband Rajiv Gandhi, her eventual entry into politics and her years at the helm of the Congress.
'Much has been written about my family'
Gandhi, 79, said the memoir is an attempt to look beyond the public mythology surrounding one of India's most prominent political families and focus on the people and emotions behind it.
"Much has been written about my family, but few narratives were able to reach into the truth of their motivations, their actions and even their very human failings," she said in a statement issued through Knopf and shared by the Associated Press.
"In many ways, this book is a homage to their humanness," she added.
Gandhi said the memoir would also offer readers her perspective on the social and political changes she witnessed during six decades in India, the country she came to regard as her own.
From Italy to India
Born in Italy, Sonia Gandhi was 19 and studying in Cambridge, England, when she met Rajiv Gandhi in 1965.
The memoir traces her early years in post-war Italy and the romance that eventually brought her to India.
Ex-PM Rajiv Gandhi, with Sonia Gandhi, met U.S. President Ronald Regan and First Lady Nancy Reagan during a state dinner for Prime Minister Gandhi in June 1985. Photo: Wikimedia Commons
According to the publisher's description, the book recounts her introduction to Indira Gandhi, her efforts to adapt to Indian life and culture, and her years raising her two children with Rajiv Gandhi while he worked as a commercial airline pilot.
The book also describes how she gradually learned Hindi, embraced saris and developed an appreciation for Indian cuisine.
Indira Gandhi's assassination changed everything
The first major tragedy described in the memoir was the death of Rajiv Gandhi's younger brother, Sanjay Gandhi, who died in a plane crash in 1980.
Four years later, on October 31, 1984, Indira Gandhi was assassinated by two of her bodyguards in the garden of her official residence in New Delhi.
The assassination transformed Sonia Gandhi's life as Rajiv, who had not initially been expected to enter politics, was thrust into the position of Prime Minister.
Rajiv Gandhi's assassination
Seven years later, Sonia Gandhi suffered another devastating loss.
On May 21, 1991, Rajiv Gandhi was assassinated during an election campaign in Tamil Nadu by a suicide bomber linked to the Liberation Tigers of Tamil Eelam (LTTE).
"It was heartbreak and loss that threw me into the public world of politics. Up till then I had guarded my privacy fiercely," Sonia Gandhi said.
Her decision to eventually enter politics would make her a major figure in Indian public life and lead to her becoming the longest-serving president of the Congress.
2004 election and decision to reject PM's post
One of the most consequential chapters of her political career came after the 2004 general election, when the Congress emerged as the largest party and formed the United Progressive Alliance (UPA).
Sonia Gandhi, who led the Congress-led alliance, chose not to become Prime Minister. Manmohan Singh instead took charge of the government, while Gandhi remained the alliance's leader from outside the government.
Sonia Gandhi with ex-PM Manmohan Singh and his wife. Photo: Wikimedia Commons
The Congress-led coalition went on to remain in power for a decade, making her decision one of the defining episodes of her political career.
'Writing about my life did not come easily'
Gandhi said writing the memoir required her to revisit experiences she had kept private for decades.
"Writing about my life did not come easily to me. It meant opening myself up, sharing moments and experiences I had always held deep inside," she said.
She added that as she gradually stepped away from the political sphere and reflected on her life, "the thread of love and loyalty" running through her experiences became clearer.
That thread, she said, connects her childhood in Italy with her life in India as Rajiv Gandhi's wife and Indira Gandhi's daughter-in-law.
Gandhi's earlier books
The memoir is not Sonia Gandhi's first literary project.
She has previously published a pictorial biography of Rajiv Gandhi and a collection of his photographs. She has also edited two volumes of private correspondence between Indira Gandhi and Jawaharlal Nehru.
'Belonging: A Journey of Love' is expected to provide a more intimate account of her personal life, family tragedies and decades in Indian politics when it is released on November 10.