'Historicalness' definitions:

Definition of 'historicalness'

noun

The state of having in fact existed in the past

noun

Significance owing to its history

From: GCIDE

historic \his*tor"ic\ (h[i^]s*t[o^]r"[i^]k), historical \his*tor"ic*al\ (h[i^]s*t[o^]r"[i^]*kal), a. [L. historicus, Gr. "istoriko`s: cf. F. historique. See History.] Of or pertaining to history, or the record of past events; as, an historical poem; the historic page. -- {His*tor"ic*al*ness}, n. -- {His*to*ric"i*ty}, n. [1913 Webster]
There warriors frowning in historic brass. --Pope. [1913 Webster]
2. having once lived, existed, or taken place in the real world; -- contrasted with legendary; as, the historical Jesus; doubt that a historical Camelot every existed; actual historical events. [WordNet 1.5]
3. Belonging to the past; as, historical (or historic) times; a historical character. [WordNet 1.5]
4. Within the period of time recorded in written documents; as, within historic times. Opposite of prehistoric.
Syn: diachronic. [WordNet 1.5]
5. (Linguistics) Same as diachronic. synchronic [WordNet 1.5]
Historical painting, that branch of painting which represents the events of history.
Historical sense, that meaning of a passage which is deduced from the circumstances of time, place, etc., under which it was written.
The historic sense, the capacity to conceive and represent the unity and significance of a past era or age. [1913 Webster]