Many famous people are believed to have been affected by bipolar disorder, based on evidence in their own writings and contemporaneous accounts by those who knew them. See list of people believed to have been affected by bipolar disorder.

There is no definitive scientific basis for classifying dead people as having had bipolar disorder, though they may very well have suffered from severe and even recurrent bouts of disordered mood. Until very recently there were no diagnostic systems with any degree of reliability. Even with the development of tools such as DSM-IV, there is a great deal of diagnostic uncertainty with living patients who have been intensively studied for decades, and there is no reason to think that it is any easier to diagnose individuals in their graves. For these reasons, some doctors regard psycho-history of this sort as a dubious endeavour.

There appears to be an association between bipolar disorder and artistic talent in many cases - this is documented in Jamison's book "Touched With Fire: Manic-Depressive Illness and the Artistic Temperament".

Some also believe that the manic state is a type of universal connection which provides creativity and intelligence but comes with the price of a soul-crushing depression

Sources:

1. Baldessarini RJ, et al. (2003). Lithium treatment and suicide risk in major affective disorders: update and new findings. J Clin Psychiatry 64 (Suppl 5), 44-52.
2. Hakkarainen R, et al. (2003). Seasonal changes, sleep length and circadian preference among twins with bipolar disorder. BMC Psychiatry 3 (1), 6.
3. Shapira A, et al. (2004). Admission rates of bipolar depressed patients increase during spring/summer and correlate with maximal environmental temperature. Bipolar Disorder Feb;6 (1), 90-3.
4. Barrett TB, Hauger RL, Kennedy JL, Sadovnick AD, Remick RA, Keck PE, McElroy SL, Alexander M, Shaw SH, Kelsoe JR. Evidence that a single nucleotide polymorphism in the promoter of the G protein receptor kinase 3 gene is associated with bipolar disorder. Mol Psychiatry. 2003 May;8(5):546-57.
5. Link and reference involving kindling theory
6. It show the promise of lamotrigine (Lamictal) in the treatment of bipolar depression.
7. It shows that gabapentin (Neurontin) is an inappropriate and ineffective medication for bipolar disorder.
8. Suicide rate of persons with bipolar disorder.