Poland would have either become part of Germany or the Soviet Union depending on the eventual outcome of World War 2.
Britain and France had offered a guarantee to Poland that if she was attacked by Germany they would come to her aid. When Germany subsequently invaded Poland, Britain and France gave Germany an ultimatum, demanding the withdrawal of German troops from Poland. Failure to do so would result in a state of war.
Britain and France
On September 1st 1939, German Forces overran Poland on land and air. Britain and France had a defence agreement with Poland and immediately demanded that German forces withdraw from Poland. Germany ignored the ultimatum, so on September 3rd 1939, Britain and France jointly declared war on Germany.
Britain had an agreement with France that if Poland was invaded they would both step in to help.
The United States wouldn't have entered World War II, or would have entered it too late causing an Allied defeat.
What happened to Poland was not affected in the least bit by the British declaring war over the German invasion of Poland. Britain was too far away to help the Poles in any way whatsoever. Germany was between Poland and Britain. So what happened to Poland would have happened if the British had not declared war. The Russians invaded Poland from the east two weeks after Germany invaded Poland from the west. Hitler and Stalin were still partners at that point, and had agreed to split Poland down the middle between them. Nobody declared war on Russia over that. I suppose having to deal with Germany first gave Britain and France all they could try to handle. Two years later Hitler obliged by turning on his partner and attacking the Soviet Union, making an "ally" of the Russians in the fight against Germany.
Nazi Germany entered Poland on September 2, 1939. Prime-minister Nevil Chamberlain issued an ultimatum to Adolf Hitler that if Poland were attacked, Great Britain would come to her aid.
On September 1, 1939 Germany invaded Poland. Great Britain and France had warned Hitler that if he invaded Poland, they would declare war.
France and Great Britain promised Poland that if Germany was ever to invade the poles, they would be on Poland's side of the war that would certainly come.
Great Britain declared war on Germany after Hitler invaded Poland. Poland was a member of the Allies, along with Britain and France, so that meant that the other allied nations would come to Poland's aid.
In the 1930's, Britain and France had a defence agreement with Poland which stated that if Poland was attacked, Britain and France would come to its aid. On 1 September 1939, German forces invaded Poland, so on 3 September 1939, Britain and France declared war on Germany.
Britain and France had offered a guarantee to Poland that if she was attacked by Germany they would come to her aid. When Germany subsequently invaded Poland, Britain and France gave Germany an ultimatum, demanding the withdrawal of German troops from Poland. Failure to do so would result in a state of war.
Britain and France
On September 1st 1939, German Forces overran Poland on land and air. Britain and France had a defence agreement with Poland and immediately demanded that German forces withdraw from Poland. Germany ignored the ultimatum, so on September 3rd 1939, Britain and France jointly declared war on Germany.
They said that they would declare war on Germany
If Hitler took Poland then Britain and France would declare war on him, which they did.
If you are asking about World War II, Britain and France had a defence agreement with Poland which stated that if Poland was attacked, Britain and France would come to its aid. On September 1st 1939, German troops invaded Poland. Britain and France demanded that Germany should immediately withdraw its troops from Poland. The German government ignored the demand so on September 3rd 1939, Britain and France simultaneously declared war on Germany.