Arguably, one of the first American television shows to successfully blend elements of comedy and drama together was Jackie Cooper's military themed series Hennesey. Although the show featured a laugh track, it also contains many elements of character drama that occurred amongst the re-occurring characters and the guest stars. The laugh track wasn't excessively used in each episode; by the third season, it was eliminated completely from the series.
While sitcoms would occasionally balance their humor with more dramatic and humanistic moments, these remained the exception to the rule as the 1960s progressed. Beginning around 1969 in the US, there was a brief spate of half-hour shows that purposely alternated between comedy and drama and aired without a laugh track, as well as some hour-long shows such as CHiPs in the late 1970s to early 1980s. These were known as "comedy-dramas".