Robert Innes discovered IC 4291 visually in 1901 using the 7-inch Merz refractor at the Royal Observatory, Cape of Good Hope. He remarked, "this is a small round nebula about 1' in diameter, brighter towards the centre." Harold Corwin notes that although Innes' description seems to refer to a small nebula or galaxy, this is a open cluster spanning 4' or 5', with a brighter core of 2'.

Paris Pismis reported it as new in her 1959 list of 24 new clusters found with the Schmidt camera at the Tonantzila observatory and noted Pismis 18 as "Six stars brighter than 10.5m to 12m; the brightness of the members gradually declines."

400/500mm - 18" (4/1/19 - OzSky): at 182x; very elongated cluster in a triangular, wedge-shaped outline with the brightest mag 10.8 star at the NE tip. There are 5 additional stars close by to the south. Another small group of stars forms the west vertex, with these stars detached from the first group by a noticeable gap or hole in the cluster. A few additional stars form the eastern side of the triangle. Perhaps 20-25 stars in total were resolved.

Notes by Steve Gottlieb