|Modern day Ukraine in white with Volhynia in gold/yellow; map courtesy of|
The Polish-Soviet War occurred between 1919 and 1921 fought by the Second Polish Republic and the Ukrainian People's Republic against Soviet Russia and Soviet Ukraine over an area that is roughly equivalent to modern-day Ukraine and the western portion of Belarus. Poland wanted to push its borders eastward as far as was feasible. And Lenin saw Poland as the bridge the Red Army had to cross to assist other communist movements bring about revolution in Europe. Ukraine was trying to establish itself as a country, but had a weak hand as Polish troops occupied much of the western part of the country. Ukraine also had to contend with the Bolsheviks pushing westward until they had pushed Polish troops all the way back to Warsaw.
Poland won an unexpected but decisive battle at Warsaw and advanced eastward. Russia sued for peace and a cease fire was put in place in October 1920. The Peace of Riga was signed on 18 March 1921 and divided the disputed territories between Poland and Soviet Russia.
The territory that included Porazava was ceded to Poland by the Riga treaty. These borders remained in place until World War II.
In between the world wars Caroline Lange's family did what families do. Her children began getting married and having children. Caroline died in October 1929 and was interred in Porazava. Her youngest son married a few months after her death, intending to use the tickets his oldest brother, Gustav (my grandfather) sent, but his new wife didn't want to leave her family, so they stayed.
Germany and the Soviet Union signed a secret pact in August 1939 called the Molotov-Ribbentrop Pact. It was a non-aggression pact between the two countries that delineated spheres of influence along Germany's easter border. On 1 September Germany invaded Poland from the west and a little more than two weeks later, on 17 September 1939 the Soviet Union invaded from the east.
Caroline Lange's five youngest children, Olga, Lydia, Richard, Heinrich, and Friedrich, found themselves in a war zone yet again.
NOTE: At this stage in my research I do not yet know why the Lange family lived in Porasava. Caroline Ludwig married Carl August Lange in 1886. Their marriage was registered in what is now Rozhysche, Volyn', Ukraine, which is south of Porazava. Carl Lange died in 1905 about three months after their youngest child was born. Caroline supported her family by working as a medicine woman and midwife.
 The Volhynia Gubernia is now located in Belarus, Poland, and Ukraine.
 Soviet Russia was a sovereign state from 1917 until 1922 when the Soviet Union was formed.
Much of the information about the various dates and places the Lange family lived comes from the few documents I have been able to collect and conversations with Friedrich Lange's son, Willy.