What was the Cassandra letter written by Lajos Kossuth?

The "Cassandra letter" was an open letter written by Lajos Kossuth in 1867, shortly before the conclusion of the Ausgleich, or Compromise of 1867, between Hungary and the Austrian monarchy.1

In this letter, Kossuth expressed his strong opposition to the reconciliation process led by Ferenc Deák. He warned of the negative consequences of the Compromise, effectively calling down "woe" upon the measure and its author. While the letter successfully stirred the opponents of the agreement, it ultimately failed to prevent the adoption and maintenance of the Compromise. The name "Cassandra letter" refers to the mythological figure Cassandra, whose dire prophecies were accurate but went unheeded.1