From Gordon Parks’ defining American Gothic to Frank Powolvy’s captivating portrait of Betty Grable and Eddie Adams’ harrowing Saigon Execution, countless photographs shot across the last 190 years have influenced history – altering our understanding of our world, impacting our governments’ policies and bearing witness to some of the world’s most important events.

Over the last three years, TIME worked with photo historians and editors, conducting thousands of interviews with photographers, picture subjects, their friends and family members and others, to present the list of the 100 Most Influential Photographs of All Time.

We asked the artist and photo editor Sanna Dullaway to colorize 30 of these iconic images.

See the full list of the 100 Most Influential Photos of All Time.

Sanna Dullaway is a photo editor based in Sweden.

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