Germany and Ireland have a taxation agreement which states in Article 14 that you are liable for taxes in a Contracting state if you spend more than 183 days there, even if your employer is from the other state.
I've been visiting my girlfriend in Germany frequently this year (A total duration of 4 months so far). I am employed by an Irish employer with no connections to Germany, but have carried out work in Germany during my 4-month visit. Throughout this time, I have been paying Irish taxes.
I've decided I wish to actually move to Germany now, however. My question is: If I officially move to Germany (and am therefore present for more than 183 days), will the 4 months of work (of which I have already payed Irish tax) be taxed?