A thread follows one event or historical theme across the archive, wherever and whenever it appears. Pick a tab to read one; they are in the order they are filed on the timeline. Pulling a thread opens up a narrowed timeline view filtered to every year that thread touches.
The contest between the Allied and European Axis powers during the Second World War for control of the Atlantic sea lanes. The campaign was defined by Germany's attempts to starve the United Kingdom into submission through submarine warfare and the Allies' subsequent efforts to combat the undersea threat.
The covert effort by the United Kingdom's Government Code and Cypher School, operating out of the Bletchley Park country estate, to break Axis communication encryption during the Second World War. Perhaps most famously, the codebreakers at Bletchley Park were able to crack the encryption created by Germany's Enigma machine, allowing the Allies to quickly decipher intercepted German messages and gain vital military intelligence.