World War I - Collecting the History through Stamps
World War I provided the largest disruption of postal services experienced since the advent of the international postal system and has long been recognised as a philatelic subject worthy of investigation by collectors.
Both during, and in the immediate aftermath of the war, the changing nature of international boundaries, and alliances, caused a huge problem for the postal systems of both the major protagonists and the countries occupied and re-occupied throughout the period.
Shipping losses, censorship and constantly moving battle fronts meant that mail movement slowed to a crawl and in some areas ceased completely. Stamp production came low in any nations list of priorities creating the need for the large numbers of surcharged and overprinted issues of the time.
As countries were occupied it became common either to surcharge that country's issues with the currency of the occupier (e.g. Romanian Bani surcharges on Hungary issues) or to surcharge the invading country's stamps with the currency of the occupied territory (e.g. Belgian Franc surcharges on German stamps). The large numbers of these modified issues, together with the emergence of new countries (such as Czechoslovakia, Yugoslavia & Poland) and the many special stamps created (Red Cross, 'War Tax' & War Orphans and other Charity types plus many local issues) make this a vast and interesting area for philatelists.