Creating the park was the personal passion of 'urban planner' Mary Henderson.  She envisioned an area full of embassies and missions and started to lobby Congress in the 1890s to create the park as an iconic entrance to the city.  George Burnap and Horace Peaslee, from the Office of Public Buildings and Grounds, created the first designs in 1914.   In 1918, landscape designer Ferruccio Vitale joined the team to develop the planting plan and simplified the design that we see today.  Source: TheGoodGarden.com