How did Louis Sullivan and William Jenney change the face of American cities in the late 1800s? They designed and built some of the early skyscrapers. They invented the electrical connections that operated streetcars. They built the Coney Island amusement parks that drew thousands. They opened some of the first settlement houses.

Louis Sullivan and William Jenney revolutionized American architecture in the late 1800s by introducing the concept of the modern skyscraper. Jenney’s Home Insurance Building in Chicago is often cited as the first skyscraper, using a steel frame that allowed buildings to reach unprecedented heights. Sullivan, known as the “father of skyscrapers,” emphasized the aesthetic beauty of these structures, famously stating “form follows function,” which became a guiding principle in modern architecture. Beyond just tall buildings, their innovations in steel and building design spurred urban growth. As cities expanded upwards rather than outwards, they transformed urban landscapes, allowing businesses to flourish in previously unused vertical space. This vertical expansion helped reshape city living, making urban areas more densely populated and dynamic, paving the way for 20th-century metropolitan centers.