In 1880, Mathilde C. Weil founded the M.C. Weil Agency, the first female-run ad agency in New York. When Weil, a German immigrant, began her career in marketing, she had been recently widowed and was working as a translator. With her creativity and talent for writing, it wasn’t long before she shifted gears to begin work as a writer.

Eventually, Weil became an editor for respected magazines and newspapers. From there, she had a straight shot to the top of her industry but realized it would be more profitable to begin a business buying and selling ad space. Mathilde C. Weil soon became known in the marketing industry as America’s first “ad woman.”

It should come as no surprise that one of the most iconic and influential marketers in US history is also one of America’s first female self-made millionaires. However, it may surprise you to find out that Madam C.J. Walker, a powerful entrepreneur, was originally born Sarah Breedlove and was the first child in her family born free after the abolition of slavery. Unfortunately, this “freedom” did not serve to keep her from hardship.

Madam C.J. Walker was orphaned as a child and worked picking cotton and doing housework. She was married at 14, had a child, and lost her husband all before the age of 20. Through it all, the young widow persevered, got an education and met “ad man” Charles Joseph Walker—the man whose name she would keep after their divorce, likely because it was a core element of her brand. While seeking a cure for her scalp condition, Madam C.J. Walker invented her own highly successful line of hair products specifically catered toward black women, a lucrative yet severely underserved market. In 1904, with only $1.25, Walker was able to launch and market her line of black hair care products and ultimately became one of America’s first female self-made millionaires.

In 1912, Christine Frederick founded the League of Advertising Women with her husband, J. George Frederick, in an effort to make space in the New York advertising industry for women. At the time, women were denied access to men’s advertising clubs. These clubs were a way to meet your peers in the industry and make meaningful connections, creative collaborations, and form long-lasting professional relationships.

For women in the industry, to be denied access to men’s advertising clubs was to be cut off from the opportunities afforded to their male peers. With the League of Advertising Women, the Fredericks gave New York’s female advertisers a fighting chance at surviving in an industry notorious for being a “boys club.” Now, the organization goes by the name of She Runs It and still helps women break into advertising, marketing, and other media industries.

If you’re not familiar with Estee Lauder, you’ve probably never stepped into a perfume or makeup aisle or seen one of their numerous television and print ads. Even if you know the name Estee Lauder, do you know the woman behind the brand? From a young age, Estee Lauder began learning the basics of how to run a business by working at the hardware store her father owned as well as her uncle’s laboratory. In the lab, Lauder began fine-tuning her uncle’s products, and in 1933, she tested them out with free demonstrations anywhere she could.

In 1946, Lauder founded her company under her own name and started selling her own refined products. And while Estee Lauder’s new, original skin-care was high quality, the secret to her success can largely be attributed to her marketing techniques. From the beginning, Lauder’s approach to marketing was innovative, involving word-of-mouth or “Tell-A-Woman” advertising as well as riding the early waves of free samples and the “BOGO” deal.

Born in 1930s North Carolina, Barbara Gardner grew up with a keen intellect and a hunger for knowledge. Gardner studied English and education at Talladega College, graduating in only three years. Later, she went on to earn additional degrees in sociology and psychology. When Gardner began to write professionally, she started at her friend’s record store, writing marketing collateral and album liner notes. Gardner was the only African American currently working in that type of role in the music industry, but her talent carried her to roles writing and editing for magazines.

Gardner’s advertising career began when she was hired by the Post-Keyes-Gardner Agency in 1964. She began going by her married name to avoid confusion with the partner named Gardner but returned to Gardner when she divorced her husband Carl Proctor in 1963. In her three years with this agency, she won 21 awards, but not every agency was a great fit. In 1969, Gardner worked first at Gene Taylor Associates, an agency that limited her to working with beauty products or household items. Later that year, she worked with the North agency, who fired her for refusing to do an advertisement for a hair care product that she found demeaning toward the civil rights movement.

All these experiences and more are what led Gardner to found her own advertising agency—Proctor and Gardner Advertising, Inc. (named prior to the couple’s divorce). With a loan from the Small Business Administration, Gardner launched and grew her business into the second-largest advertising agency in the United States.

Caroline Robinson Jones graduated from the University of Michigan before going on to work at prominent advertising agency J. Walter Thompson. In 1977, she was hired as the first black woman VP at a major BBDO advertising agency. After breaking the glass ceiling and climbing through, she reached down to lift others up with her.

Fighting for change, fair treatment, and better representation for people of marginalized identities, Jones came up against a lot of pushback but never backed down. Throughout her career, Caroline worked with big-name brands like Miller High Life and Goodyear. She also went on to find several successful firms, including Caroline Jones Advertising, Mingo-Jones, and Zebra Associates, some of the first firms created by African-American women to focus on minority advertising.