Merging tables from two different databases (Python)

I have two databases Database1.db and Database2.db. The databases contain tables with matching names and matching columns (and the Primary key is the 'Date' column in both). The only difference between the two is that the entries in Database1 are from 2013 and the entries in Database2 are from 2014. I would like to merge these two databases so that all the 2013 and 2014 data ends up in one table in a third database (let's call it Database3.db).

To be clear, here is what the databases I'm working with currently contain and what I want the third resulting database to contain:

Database1.db:

Table Name: GERMANY_BERLIN

Date            Morning    Day     Evening    Night
01.01.2013      0.5        0.2      0.2       0.1
02.01.2013      0.4        0.3      0.1       0.2
...

Database2.db:

Table Name: GERMANY_BERLIN

Date            Morning    Day     Evening    Night
01.01.2014      0.6        0.2      0.1       0.1
02.01.2014      0.5        0.2      0.3       0.0
...

I would like to have create a resulting Database3 with the following data:

Database2.db:

Table Name: GERMANY_BERLIN

Date            Morning    Day     Evening    Night
01.01.2013      0.5        0.2      0.2       0.1
02.01.2013      0.4        0.3      0.1       0.2
01.01.2014      0.6        0.2      0.1       0.1
02.01.2014      0.5        0.2      0.3       0.0
...

I haven't been able to find anything directly helpful on this online yet (perhaps JOINS could be used somehow? bhttp://www.tutorialspoint.com/sqlite/sqlite_using_joins.htm) so any suggestions would be greatly appreciated!

PS. SQLite has been used to create the existing databases and is the database-related Python library that I'm most familiar with