Quick answer: organised cheerleading is generally traced back to the late 1800s, with the late 1890s most commonly cited as the point when American colleges began appointing students to formally lead crowd chants - the activity we'd recognise as the earliest form of cheerleading.
The Late 1800s Starting Point
Crowd noise at American college sports existed before any organised role for leading it, but historians and cheer organisations generally point to the final years of the 19th century as the moment "yell leading" became a defined, organised activity, with specific students taking on the role in front of the crowd. See Who Invented Cheerleading? for the most commonly cited individual moment within this period.
Early 1900s: Formalisation
Through the early 20th century, yell leading spread to more colleges and became more structured, with recognised squads and, eventually, organised tryouts - though it remained closely tied to supporting football and other college sports rather than existing as its own event.
Mid-1900s: Growth and Change
By the mid-20th century, cheerleading had grown significantly in scale and had shifted from a male-dominated activity to one performed predominantly by women - see When Did Women Start Cheerleading? for that part of the timeline - while also incorporating more athletic elements like jumps and eventually tumbling.
Late 1900s: Toward Competition
From the mid-to-late 20th century onward, cheerleading increasingly split into sideline cheer and competitive cheer, with the latter eventually becoming judged in its own right rather than existing purely to support another sport. See When Did Cheer Become a Sport? for more on this shift.
A Note on Dates and Sources
Precise dates for early cheerleading milestones vary between sources, since much of this history is preserved through institutional and oral tradition rather than extensive contemporary documentation. Where a specific date matters to you, we recommend cross-checking it against a dedicated historical source - see our sources page.