Final answer:
The weaker parties during the time period from 1800 to 1860 were the Whigs and the Know-Nothing Party.
Step-by-step explanation:
During the time period from 1800 to 1860 in the United States, the weaker parties were the Whigs and the Know-Nothing Party. The Whigs entered a period of decline after the 1852 election and eventually ceased to exist as a national party. Several new parties emerged to take their place, with the Know-Nothing Party being one of the notable ones.