There were many ways varying from plain sabotage where they claimed that the Portuguese merchants were thieves, up to more controversial means such as ordering their assassinations and telling the king that he should have them killed because they didn't give him presents and plan to enrich their wealth at his expense.
The Mississippi was used for transportation and their were ports along it before the LA purchase
Ethiopia purchased modern weapons from France and Russia.
Ethiopia won its wars against Italy and has successfully secured its sovereignty because they bought some artillery pieces from Russia. Russia also supported Ethiopia with military advisers and army training. United Kingdom and France also supported Ethiopia to prevent Italy from becoming their colonial competitor.
