(CNN) - Daniel Cardwell’s obsession consumed three decades of his life and $250,000 of his money, he estimates. His energy has been devoted to answering one basic question: “Who am I?”
Cardwell was a “brown baby” - one of thousands of children born to African-American GIs and white German women in the years after World War II. Inter-racial relationships still weren't common or accepted among most in the United States or Germany, and they weren't supported by the military brass, either.
Couples were often split apart by disapproving military officers. Their children were deemed "mischlingskinder" - a derogatory term for mixed race children. With fathers forced to move way, the single mothers of the African-American babies struggled to find support in a mostly white Germany and were encouraged to give their kids up.
Thousands of the children born from the inter-racial relationships were put up for adoption and placed in homes with African-American military families in the United States or Germany. Images of black, German-speaking toddlers with their adoptive American families were splashed across the pages of Jet and Ebony magazines and African-American newspapers.
Their long-forgotten stories have recently been shared in new films, "Brown Babies: The Mischlingskinder Story," which was released last summer and "Brown Babies: Germany's Lost Children," which aired on German television this fall.
The hunt for his biological parents - and his own sense of identity - has dominated the second half of his life. He has traveled the country in search of aging documents, tried hypnotism therapy, built relationships with distant family members and visited Germany several times.
“Would I do it all again? Yes,” Cardwell said. “If only so others wouldn’t have to go through what I went through."
Between 2 and 3 million African-American civilian personnel, military members and their families lived in Germany from 1945 until the end of the Cold War, according to the digital archive "The Civil Rights Struggle, African American GI's, and Germany."
Many German women perceived the black soldiers to be kinder than their white counterparts, even admiring - a rarity after the brutal war. After so many years of scarcity, a gift of stockings or canned milk might as well have been a diamond ring.
The soldiers wanted to seize the advantages of being away from Jim Crow America. In Germany, they could go to a biergarten, dance with a German woman at a bar and - if they ignored rules against fraternization - develop a relationship with her.
The total number of children born from those relationships is unclear. Some 5,000 "brown babies" were born between 1945 and 1955, according to the book “Race After Hitler: Black Occupation Children in Postwar Germany and America," and by 1968, Americans had adopted about 7,000 of these German children, the book's author, historian Heide Fehrenbach, wrote. Still more of those kids remained in Germany.
But after the babies were born and the soldiers' superiors discovered the romances, they often transferred the black soldiers to other bases. The U.S. military's policy at the time was to reject any claims of paternity made by German mothers. Black soldiers who wanted to marry their white girlfriends were often forbidden from doing so.
Life wasn't simple for the mothers, either - they were sometimes judged unfit by child welfare officials based solely on the fact that they had a relationship with an African-American man. Some Germans condemned the mothers as "negerhueren" - Negro whores.
German authorities doubted the children would thrive in the country, where national identity was strongly tied to white German heritage. It became common for the babies to be adopted to couples living in the United States, where the children’s roots were hidden, often for years. Many didn’t know of they had been adopted until they were adults.
Cardwell remembers his adoptive parents as cold and distant. He spent years at boarding schools, then later returned to their home, where he worked on their farmland. He can't remember being hugged, or told that they loved him.
It wasn't until he began trying to find his biological parents that he discovered his mother was actually a half-German refugee from Poland. She thought she was leaving him at an orphanage temporarily, and had searched for him for years. He learned, too, that his father was described as “colored” in official papers, and was a mixture of Portuguese, native Hawaiian, Japanese and Puerto Rican ancestry.
Regina Griffin, a Washington-area journalist, was inspired to make "Brown Babies: The Mischlingskinder Story,"after a "brown baby" and family friend wrote a book about her search for her parents. Griffin realized most people had never heard the adoptees' remarkable stories, so she interviewed "brown babies," German mothers, historians, and the African-American fathers.
“It’s a part of our history,” Griffin said. “It’s not just African-American history, it’s not just American history, it’s world history. There were a lot of people who were caught between two countries, two warring nations. And we allowed those children to be abandoned, and people should know that.”
For the thousands of children who are now adults and seeking their biological families, time is running out. Henriette Cain, a "brown baby," from Rockford, Illinois, knows this all too well.
“People’s mothers are passing away, their fathers are passing away, and people are starting to wonder who they are,” Cain said from her home. “Now even we are passing away, and it’s a story that needs to be told.”
Since beginning her search in the 1970s, the 59-year-old retiree has been fortunate - she located and met her biological sister, who was living in Darmstadt, Germany, and her biological mother, who had married a white U.S. soldier and moved to Virginia. The family now enjoys a close relationship. She tracked down her biological father, as well, but he died before they could meet.
Cain discovered that her mother had never really wanted to give her up. Her biological father had been reassigned to another military base, and promised to return to bring his family to the United States, but they never heard from him again.
Her mother found herself alone and impoverished in post-war Germany, with two young daughters, an unsupportive family and a choice to make: Keep the children and face poverty and scorn, or put them up for adoption in hopes of giving them a better life.
Cain’s older sister was adopted by the family with whom they had been living while Cain was sent to a local orphanage. When she was 2, she was adopted by an African-American couple living at a U.S. base nearby.
Her adoptive parents doted on her, and she was happy, but she always sensed she was different. Her adoptive parents were much darker in skin tone. They didn't reveal that she was adopted until she was 12. Children she grew up with taunted her and called her “Little Nazi.”
Soon after reuniting with her birth family, Cain began helping other adoptees. She now runs Sunco Public Records Research, a firm that helps black German adoptees, American fathers and German mothers find each other.
Cain said about 25 of her last 40 searches ended with a reunion or positive identification. She has about seven cases that remain open.
“Since I’ve been in their position, I understand how they feel and I know it’s important to get the answers for them,” Cain said.
Cardwell is still looking for answers.
After years without all the information he's looking for, he now sees America and Germany’s obsession with skin color as a destructive force in his life.
“My mother couldn’t marry my father because of color. I couldn’t stay in Germany because of color. Here in America they couldn’t figure out my color,” Cardwell said. “Maybe I should just be an American and just let it be with that. They won’t let me be German.”
Nevertheless, he continues to search for more clues about his father’s identity. Because he’s officially an illegitimate child, he can’t view his biological father’s military records and other papers until they become available to the general public. He's working on a book about his life. He helps other adoptees in their searches.
“My whole objective in this thing is to minimize the pain that I felt for so long,” Cardwell said. “I have come to know that there were a number of mothers that did love their children, and a number of fathers who did want those children, but because of color they weren’t allowed to have them.”