Last Monday, a 17-year-old apparently inspired by terror group Isis attacked passengers with an axe on a train in Würzburg, Bavaria. It was to be the first act in a week of violence arguably unprecedented in modern German history.
On Friday, an 18-year-old went on a shooting rampage at a shopping centre in Munich, killing nine other people.
Sunday saw two more attacks. In the afternoon, a man with a kebab knife killed one and injured several others in Baden-Württemberg. Later that evening a suicide bomber blew himself up in Ansbach, a Bavarian town near the site of Monday’s axe attack, injuring 15 people. The fact that the bomber was rejected from entering a crowded music festival nearby likely avoided more serious casualties.
The attacks don't seem to be directly related to one another, but there are certain consequences which some or all of them will almost certainly have.
The refugee angle
Three of the four attacks were carried out by people who had come to Germany as refugees. The Würzburg axe attacker is believed to have come from Afghanistan. The man who attacked people in Reutlingen on Sunday was a 21-year-old Syrian asylum seeker. The Ansbach suicide bomber came to Germany from Syria in 2014. His asylum claim had been rejected.
Last year Germany took in hundreds of thousands of refugees from war-torn regions such as Syria, Iraq and Afghanistan. These attacks will inevitably increase the already high feelings of public insecurity that this influx has created.
Public opinion turned strongly against the welcoming culture after sexual assaults in Cologne and Hamburg over New Year, around half of the suspects for which arrived as refugees over the preceding 12 months.
The great influx of refugees which took place in the second half of 2015 came to an end months ago, with monthly arrivals now comparable to the numbers that crossed the border in a single day in November 2015.
These attacks will very likely make that trend irreversible, even as terrorism and civil war continues to plague Syria and Iraq.
Bavarian Interior Minister Joachim Herrmann said on Monday that the state needed to “act decisively” against asylum seekers who pose a threat to Germany.
What exactly this means though is far from clear. A court recently forbade the state from deporting an ex-bodyguard of Osama bin Laden to Tunisia because the threat to his safety there would be too great.
It is therefore unlikely that dangerous refugees from Afghanistan or Syrian could be sent back to their home countries.
The terrorism angle
Bavarian investigators say that it is highly likely that the suicide bombing on Sunday evening was an Islamist attack. It is easy to see why they have come to this conclusion - ‘martyrdom operations’ of this nature are a hallmark of jihadi groups.
On the other hand it is possible that the man could have been acting out of revenge for the fact that his asylum application was rejected, Stefan Meining, a terrorism expert with Bayerische Rundfunk said on Monday.
As yet, no evidence has been found to suggest the 27-year-old was linked to Isis or a similar organization, but ongoing searches of his room at an asylum centre could change this.
The 17-year-old in Würzburg also had a handmade Isis flag in his room, but investigators believe that he was inspired by the group rather than directly groomed or instructed by them.
The other two attacks appear to have no connection to terrorism. The Munich gunman was a bullied loner inspired by previous school shootings. People who apparently influenced him include a white supremacist and school shooters, judging from material found in his home and on his computer. But that fact isn't likely to stop the far right from trying to turn the discussion into a race debate due to the shooter's Iranian heritage.
The man who attacked people with a kebab knife in Reutlingen also appears to have acted for purely personal reasons. Reports suggest that he was in love with the Polish woman who he killed, and witnesses saw the two arguing before the attack. Since he grabbed the knife from the fast food restaurant in which he worked, it appears that the attack was not planned.
That the Würzburg attack and the Ansbach bombing happened so soon after the bloodbath in Nice suggests that they could be part of an orchestrated campaign, argues Die Welt.
At this stage there is no evidence to suggest that is the case. But that won't stop people feeling unsettled.
Last week, polling showed that roughly three quarters of Germans expected a terrorist attack to hit the country in the near future. The Ansbach suicide bombing may well prove to have been that attack.
The mental health angle
Two of the attacks were carried out by people with a record of mental health problems. The teenager who murdered nine people in Munich had spent several weeks in psychiatric care last year. Police have also said that the Ansbach suicide bomber spent time in psychiatric care after twice attempting suicide.
Questions are already being asked about what can be done to improve mental care to make this type of attack less likely.
The Action Association Winnenden, set up after a bloody school massacre in 2009, called on Monday for more to be done to detect warning signs in teenagers, saying that the attackers were often very irritable and withdrawn.
A journalist for the Süddeutsche Zeitung, who spoke to pupils at the Munich attacker's school, says students told her that he threatened to kill classmates, suggesting a possible failure to read the warning signs.
Bavarian interior minister Joachim Herrmann however said that doctors at the psychiatric ward where the adolescent was treated had no indication that he intended to harm other people.
After the Würzburg axe attack, the culprit of which was a refugee who came to Germany as an unaccompanied minor, Marianne Burkert-Eulitz, the Green Party's spokesperson for Family, Youths and Children, told Tagesspiegel there were "substantial shortcomings" in the care of unaccompanied minors.
Björb Eggert, youth spokesperson for the Social Democratic Party (SPD) in Berlin, also said that the state needs to look into innovative ways to spot psychological warning signs in young people as youths are often reluctant to seek help themselves.
The security angle
Debate is now raging in Germany on what security measures can be taken to try and prevent murderous rampages.
Last week the German Police Union (DpolG) called for a bigger security presence on trains.
Complaining that the police presence at train stations has been severely cut down in recent years, the chairman of the union Ernst Walter claimed that “if we continue to be pulled back from these areas we won’t have a means of countering these attacks.”
We also now know that the German army (Bundeswehr) were on standby on Friday night in Munich as unconfirmed reports suggested that attacks might have been taking place at various locations throughout the city.
“As long as the situation in Munich on Friday was unclear, a military police unit was on standby,” Defence Minister Ursula von der Leyen told the Frankfurter Allgemeine Zeitung.
Von der Leyen has argued that the German constitution allows for military action when attacks are taking place in several places at the same time.
But critics say that the army is neither trained nor equipped to deal with internal terror situations.
Questions are also being asked about whether security services could have prevented some of these attacks by intercepting communications.
Die Welt reports that the Würzburg attacker used pseudonyms on Facebook. The Munich gunman also bought his weapon on the darknet and extensively researched the subject of gun rampages.
Stefan Mayer of the CSU has called for the state to do more to fight the online weapons trade, saying that a tightening of Germany's gun laws which he described as among the strictest in Europe, would not be productive.
On Monday Munich's mayor also called for rucksacks to be banned at Oktoberfest, suggesting Germans will have to get used to tighter security checks at public events.
All in all, it seems inevitable that this string of violence will change life in Germany; the only question being whether these changes will be enough to prevent further attacks.